5. (C)
Question Type: Assumption
What if the items being dumped were actually food items? Couldn’t the ants have been emptying the dumping site and taking food particles to their neighbors simultaneously? Atrens assumes that the dumped items were not food. Answer (C) clearly expresses this assumption.
(A) is out of scope (human interactions?).
(B) is out of scope. Whether or not the ants were giving food gifts is in question, but their capacity to receive and make use of gifts is irrelevant.
(D) is wrong because the reception of the food gifts is irrelevant and out of scope.
(E) is irrelevant as well. It doesn’t matter if the entomologist changed his mind. What’s at play in this argument is whether he/she was right or wrong the first time.
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