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: Litters contain from one to ____ kittens, and tend to be much larger when prey is abundant.\Question: Choose the right answer from options given a) three b) four c) two d) seven

A: b
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Q: Atoms are extremely small, on the order of a few ____ billionths of a meter.\Question: Choose the right answer from options given a) ten b) seven c) nine d) eight

A: a
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Q: Women are about ____ times more likely to develop osteoporosis than men.\Question: Choose the right answer from options given a) ten b) seven c) two d) four

A:
d
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