Quiz
Simulator EXIN Blockchain Foundations
Create a free account to finish this quiz
Save your progress and see your final score.
Already have an account? Sign in
Questions in this quiz (40)
1What is an advantage of a public blockchain?
- AIt does not use disinterested third parties to secure blocks, as all participants have a vested interest
- Bt is more resilient against fraud, because it uses federated nodes to combat fraud.
- CIt is open to everyone in the world without permission and licensing requirements.
- DIts networks are built by for-profit companies and the working of the network is guaranteed.
2What is a blockchain?
- AA centralized database that holds a subset of all transactions on all nodes.
- BA client-server database existing on a limited number of nodes at the same time.
- CA distributed database with a record of all transactions on the network.
- DA standalone database with history of all transactions on various nodes.
3What is the function of a lightweight node within a blockchain network?
- AIt stores a complete history of every transaction on the network.
- BIt stores purchased cryptocurrency for users of a blockchain network.
- CIt verifies transactions by piggybacking on the work of full nodes.
4What is not a classification for a node?
- AFull node
- BLightweight node
- CMerkle node
- DMiner node
5A bearer instrument used to transfer value between two parties over a blockchain network. What is this instrument?
- AA DApp
- BA hash
- CA node
- DA token
6What is a key characteristic of a public blockchain?
- AAllowing a user to elect nodes to process transactions
- BAllowing anyone to participate in the blockchain network
- CAllowing control over who can participate and at what level
- DAllowing only trusted parties to operate their blockchain
7What is an example of the use of cryptography in a blockchain?
- AAccessing private or hybrid blockchains by using a private key
- BCreating cryptocurrency as a reward for mining nodes
- CKeeping blockchains secure from 51% attacks by corrupt nodes
- DSecuring transfers of cryptocurrency between recipients
8How do blockchains use private and public-key cryptography?
- AAsymmetric encryption allows a sender to transfer cryptocurrency to a public key. The recipient can then access these funds with their private key and hold it in their wallet.
- BIn public-key cryptography, one key is used to encrypt and decrypt transaction. The sender uses this key to send cryptocurrency and the recipient’s wallet holds it after decryption.
- CSymmetric encryption allows a sender to transfer cryptocurrency to another user. The recipient can then access their funds when the sender grants access to their private key.
- DThe algorithm in the blockchain encrypts and stores private and public keys to all user's wallets. The user then accesses their funds through their twenty-word passphrase key.
9How do hybrid blockchain networks combat 51% attacks?
- AThrough a central controller ensuring the security of each node in the network
- BThrough a Proof of Work (PoW) algorithm, which allows miners to secure the network
- CThrough incentivization, where miners receive currency for securing the network
- DThrough Merkle tree roots, that allow the network to restore itself to its last valid block
10How do blockchains function like ledgers?
- AThey hold a record of all transactions that have ever occurred on a network.
- BThey hold vast amounts of transaction data as a centralized database.
- CThey periodically update all balances of each wallet to the blockchain.
11What is the task of miners in a blockchain network?
- AMiners act as a single third party to aggregate records and provide trust in the network by the miners’ authority.
- BMiners are computers that allow access to the blockchain, ensuring the number of corrupt nodes will stay low.
- CMiners are nodes that compete for a reward by calculating the correct nonce to make a transaction possible.
- DMiners determine the consensus rules that should be followed and interfere when these rules are broken.
12Which description fits only the Proof of Work (PoW) consensus algorithm?
- AA collaborative consensus algorithm, where approved accounts do the validation.
- BA collaborative consensus algorithm that is facilitated by farmers, who offer leftover memory of their computer to make transactions possible.
- CA consensus algorithm, where the validation is done for the entire transaction flow, including not only the correctness, but also the sequence of transactions.
- DA low-cost and fast algorithm, where a node needs to deposit cryptocurrency to guarantee the transaction.
- EA noncompetitive consensus algorithm, where validation is done by elected nodes, which send cryptocurrency to an address, from which it cannot be retrieved.
- FAn algorithm that involves collaborative validation, performed by validators, which are chosen outside of the consensus.
- GAn algorithm that works in a trusted execution environment and proves the time when the transaction has taken place.
- HAn intensive and expensive, competitive algorithm where each mining node on the blockchain is competing to secure blocks.
13A competitive consensus algorithm that was developed because blockchains had difficulty meeting the transaction speed demands. Which consensus algorithm is this?
- ADelegated Proof of Stake (DPoS)
- BProof of Burn
- CProof of Stake (PoS)
- DProof of Work (PoW)
14Which consensus algorithm is the least energy efficient?
- ADelegated Proof of Stake (DPoS)
- BProof of Authority (PoA)
- CProof of Space (PoSpace)
- DProof of Work (PoW)
15What is an advantage of using the consensus algorithm Proof of Elapsed Time (PoET) instead of Proof of Work (PoW)?
- APoET can often be used in a permissionless blockchain more easily than PoW, because PoET’s lottery system for node selection is secure.
- BPoET has generally lower transaction costs than PoW, because the hardware needed is more generic than the hardware needed for PoW.
- CPoET is much more secure than PoW, because PoET supports the trusted execution environment (TEE) by time-stamping the transactions.
- DPoET is usually faster than PoW, because fewer nodes compete for validation than in PoW, since PoET randomly selects the nodes.
16An attacker tries to corrupt the transaction history of a blockchain to be able to spend a token or a cryptocurrency twice. What is the most likely thing this attacker did?
- AThe attacker changed the transaction on his node and propagated it in the network.
- BThe attacker edited the smart contract and recovered investor’s cryptocurrency.
- CThe attacker gained control of more than 51% of the network’s computing power.
- DThe attacker hard-forked the network and created a new blockchain network.
17Blockchain networks are vulnerable to 51% attacks. Which network would incentivize hackers most to break the network?
- ABitcoin
- BFabric
- CFactom
- DRipple
18One of the greatest threats to the blockchain community is the narcissism of small differences. What is the result of this narcissism of small differences?
- AOne community group makes fun of another community group over small differences, resulting in greater collaboration.
- BThe community cares about and works to resolve small differences that cannot be perceived by outside groups.
- CThe community has developed many similar projects and these fight with one another over small differences.
- DThe community has grown closer and works together in a collaborative fashion to solve common problems.
19How do fraudsters use a Ponzi scheme?
- AA fraudster convinces a victim to pay for receiving something of greater value later on.
- BA fraudster finds investors, then dumps the tokens of the investors to crash the market.
- CA fraudster pays dividends to initial investors using the funds of subsequent investors.
- DA fraudster steals credit cards and uses them to buy money, goods or property.
20Which characteristic of a blockchain network is also its protection?
- AThe greater the number of full independent nodes, the harder it is to compromise the data in the blockchain.
- BThe lower the number of miners in the blockchain, the higher the incentive is for securing the network.
- CThe more centralized the control of the blockchain is, the harder it is to secure the data and avoid fraud.
- DThe more complicated the Proof of Work (PoW) algorithm is, the more rewarding it is to secure the network.
21How can information be secured in a blockchain?
- ABy using a closed peer-to-peer (P2P) network, sharing information across platforms
- BBy using a distribution of cryptocurrencies over miners through the network
- CBy using asymmetric cryptography, consisting of a public and private key
- DBy using distributed ledger technology (DLT), which records transactions at the source
22In what way do blockchains use a public witness?
- AA digital courthouse or library acts as a public witness to store information to reference.
- BA node on a blockchain network attests to the accuracy and truthfulness of information.
- CA person sends a transaction over a public network to earn rewards as a public witness.
- DA preferred node can be elected to attest to the accuracy and truthfulness of information.
23Blockchain enables self-sovereign identity. How does blockchain do this?
- AIt enables centralized third parties to offer easy-to-use and valid identity information.
- BIt enables each person to have exclusive control of their money, property and identity.
- CIt enables governments to effortlessly issue identities with advanced digital certificates.
- DIt enables only internet companies to offer world-class secure personal identity repositories.
24Public blockchains give an incentive to encourage users to mine blocks and secure the network. What incentive is this?
- APublic blockchains allow users to create tokens to sell on secondary markets.
- BPublic blockchains do not offer rewards, because they are open source.
- CPublic blockchains offer cash rewards for running mining nodes.
- DPublic blockchains offer rewards for mining in the form of cryptocurrency.
25What is a key characteristic of the Hyperledger network?
- AIt is a public blockchain network and one of the oldest networks, existing since 2009.
- BIt is private, open sourced and can run everyone’s own distributed ledger technology (DLT).
- CIt utilizes cryptocurrency as a reward mechanism, which makes the network more secure.
- DIt utilizes the Proof of Stake (PoS) consensus algorithm as its main security measure.
26An organization wants to develop smart contracts, based on blockchain technology. The organization does not wish to burden employees with maintaining the security of the blockchain. What blockchain technology fits the organization best?
- AA hybrid blockchain
- BA private blockchain
- CA public blockchain
27What is the best use case for smart contracts?
- ADigitalize and automate legally binding contracts using artificial intelligence (AI)
- BEnforce the execution of contracts in the legal system using cryptocurrencies
- CEnsure automatic payments by predetermined actions or events in insurance contracts
- DExtend the Bitcoin blockchain, the best-known smart contract platform, to the judicial system
28In which scenario is a smart contract the best solution to the problem?
- AA bartender wants to force customers to pay for their drinks by transferring cryptocurrency to his wallet.
- BA chief financial officer wants her smart watch to notify her when her partner enters their front door.
- CAn energy company wants to automatically buy power when the price reaches a predetermined rate.
- DAn insurance company wants to pay out a farmer whenever the case manager feels it is best to do so.
29What are DApps designed to do?
- AExecute smart contracts with the business logic in the front-end of a standalone application
- BManage cryptocurrencies only, without any embedded voting system for governance of the blockchain
- CRun applications on a peer-to-peer (P2P) network expanding smart contracts beyond simple value transfer
- DSupport applications that run on multiple public cloud providers avoiding any vendor lock-in and fraud
30What is the role of a DAO (decentralized autonomous organization)?
- AAddress the principal-agent dilemma with collaboration and acceptance of actions within agreed rules
- BEmbed regulated online smart contracts with the current judicial system, using public blockchains
- COffer complex online smart contracts without any link to tangible and intangible offline assets
- DProvide a private blockchain contract platform on which users can run their online applications
31How can blockchain technology best help securing identity data?
- ABy eliminating third parties through providing secured-data storage at a user’s server
- BBy encoding all the health data and save it on a private and permissionless blockchain
- CBy protecting data that has been submitted on the internet using a cryptographic algorithm
- DBy providing information personal data without disclosing the actual data that proves it
32What is the value of using blockchain networks with Internet of Things (IoT)?
- AAllowing blockchain users to follow self-driving cars and access these cars
- BAvoiding a spoofing attack using the secured identity that is stored on a blockchain
- CEnabling software that programs itself to solve problems without human intervention
- DSolving expensive and complex calculations using Hyperledger Fabric mining
33Blockchain technology has made decentralized marketplaces possible. What is a benefit of a decentralized marketplace?
- AIt is based on open-source technology, so it can be used without any investment.
- BIt is not under a paid license to operate and therefore it is managed better.
- CIt is relatively cheap due to the use of cryptocurrency and is very accessible.
- DIt is tamper-proof, resilient to being shut down and trustworthy due to smart contracts.
34How does blockchain improve supply chains?
- ABy automatically creating trade agreements between two parties
- BBy creating safe centralized marketplaces to trade goods on
- CBy stabilizing the national currencies of the countries involved
- DBy transferring tokenized ownership through a software system
35The Monetary Authority of Singapore (MAS) and blockchain company R3 partnered together. What did they achieve together?
- AThe creation of smart contracts and stable coins
- BThe facilitation of interbank transmission of messages
- CThe first interbank payments without limitations of time zones
- DThe launch of wire transfers using cryptography
36What is digital fiat currency?
- AA digital form of currency, that represents a country’s financial reserves
- BAn e-currency, that creates a transparent and borderless debt market
- CAn online system, that enables making transactions without a bank account
37How does blockchain technology benefit the insurance industry?
- ABy avoiding compliance requirements of national authorities, which reduces overhead
- BBy ensuring accuracy of data and automating micro insurances, which reduces costs
- CBy introducing flexible premiums to be paid by customers, which increases profits
- DBy setting up a digital mode of payment, which simplifies claims settlement
38How does blockchain technology help to protect intellectual property rights (IP)?
- AIt allows a user to include IP transactions in smart contracts.
- BIt allows a user to record an event and establish the timeline.
- CIt allows a user to record the creation of software packages.
- DIt allows a user to send a transaction and receive IP ownership.
39What is an example of how a government is actively promoting the use of blockchain?
- AChina has created a regulatory sandbox that allows them to closely monitor the experiments in blockchain mining and create their own cryptocurrency.
- BEstonia offers e-Residency software, which is available to anyone in the world interested in operating a business online and from within the European Union.
- CSingapore’s Monetary Authority (MAS) is creating central bank digital money for payments between banks using distributed ledger technology (DLT).
40Why is blockchain described as the technology that adds a layer of trust to the internet?
- AIt allows individuals and groups to work together without having to trust each other or establish authority.
- BIt creates a dedicated virtual private network (VPN) tunnel between two or more parties to carry out online fund transfers.
- CIt provides mechanism for the government to create their own digital fiat currency as a replacement of physical currency.
- DIt provides multifactor authentication to create and update records of cryptocurrency transactions securely.
Information
- Description
- Curso Interno de Empresa EXIN Certifications Quiz on Simulator EXIN Blockchain Foundations, created by Maddox Doza on 19/01/2021.
- Author
- Maddox Doza
- Language
- English
- Views
- 0
- Tags
- Rating
- No ratings yet Rate this quiz