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: Toucanets encompass ____ genera.\Question: Choose the right answer from options given a) seven b) six c) two d) one

A: c
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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: Bronze is made by mixing ____ parts copper to one part tin.\Question: Choose the right answer from options given a) zero b) five c) three d) nine

A:
c
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