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: Organisms have ____ forms of nucleic acid.\Question: Choose the right answer from options given a) four b) three c) two d) one

A: c
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Q: All birds have ____ legs with four toes each.\Question: Choose the right answer from options given a) zero b) one c) three d) two

A: d
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Q: Every bounded function is the sum of ____ almost continuous bounded functions.\Question: Choose the right answer from options given a) eight b) ten c) three d) five

A:
c
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