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: Gravity is the force that brings ____ objects together .\Question: Choose the right answer from options given a) five b) two c) one d) nine

A: b
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Q: Some sources claim there are more like ____ million vertebrate animals in zoos.\Question: Choose the right answer from options given a) six b) five c) one d) three

A: b
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Q: Sexual maturity is reached within ____ to four years.\Question: Choose the right answer from options given a) ten b) two c) six d) zero

A:
b
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