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: Springtails reproduce quickly usually within three to ____ weeks.\Question: Choose the right answer from options given a) five b) six c) nine d) three

A: a
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Q: Potential energy is divided into ____ different types of energy.\Question: Choose the right answer from options given a) eight b) three c) zero d) two

A: b
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Q: Blood pressure is measured using ____ numbers.\Question: Choose the right answer from options given a) two b) ten c) three d) no

A:
a
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