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: Living cells have at least ____ parts.\Question: Choose the right answer from options given a) seven b) three c) zero d) four

A: b
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Q: Pairs encodes all sets of objects with ____ components.\Question: Choose the right answer from options given a) ten b) five c) two d) no

A: c
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Q: Purine synthesis requires ____ components of the one-carbon pool.\Question: Choose the right answer from options given a) two b) no c) three d) five

A:
a
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