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: Casinos have no windows and they have ____ clocks.\Question: Choose the right answer from options given a) six b) four c) eight d) no

A: d
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Q: Sexual reproduction involves ____ parents, one male and one female.\Question: Choose the right answer from options given a) zero b) two c) nine d) four

A: b
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Q: Rabbits can mate from ____ to seven times a year.\Question: Choose the right answer from options given a) six b) two c) five d) three

A:
d
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