This question is worded incorrectly. In the absolute sense--that is, the classification which all primates share--the correct answer would be order, as all primates are in the order Primates. In the smallest sense (the classification which humans are in with at least one primate) the answer is species, as humans are animals in the order Primates, and therefore are Primates.
This blunder undermines the integrity of resources such as GoConqr. Please take time in the future to check the accuracy of the information presented.