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: Eastern cottontails have ____ different fur coats each year.\Question: Choose the right answer from options given a) five b) two c) eight d) six

A: b
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Q: Many tortoises can retract their head, their ____ limbs and tail into the shell for protection.\Question: Choose the right answer from options given a) no b) one c) two d) four

A: d
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Q: Chemotherapy is given in cycles - for example, a dose every ____ to four weeks.\Question: Choose the right answer from options given a) one b) six c) no d) three

A:
d
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