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: Plants can uptake ____ times more nutrients, and improve soil texture at the same time.\Question: Choose the right answer from options given a) no b) two c) three d) ten

A: d
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Q: Most pregnant women have ____ problems in their pregnancies or deliveries.\Question: Choose the right answer from options given a) ten b) zero c) no d) seven

A:
c
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