Given a sentence with a missing word, pick the answer option that best fills out the missing word in the sentence. Indicate each answer with its index ('a', 'b', 'c', 'd').

Q: Aridity presents ____ main obstacles to solitary behavior.\Question: Choose the right answer from options given a) no b) three c) two d) five

A: c
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Q: Eastern cottontails have ____ different fur coats each year.\Question: Choose the right answer from options given a) five b) two c) eight d) six

A: b
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Q: Wild birds fall into ____ different groups of feeders.\Question: Choose the right answer from options given a) one b) two c) three d) six

A:
c
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