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: Tetrapods are animals that have ____ legs or leg-like appendages.\Question: Choose the right answer from options given a) four b) one c) ten d) six

A: a
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Q: Diploid cultivars have ____ alleles.\Question: Choose the right answer from options given a) eight b) six c) two d) five

A: c
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Q: Lung disease is America's number three killer, responsible for ____ in seven deaths.\Question: Choose the right answer from options given a) five b) nine c) one d) four

A:
c
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