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: Cigarette smokers are ____ times more likely to die of lung cancer than nonsmokers.\Question: Choose the right answer from options given a) ten b) six c) four d) nine

A: a
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Q: Elephants give birth to one calf every ____ to nine years on average.\Question: Choose the right answer from options given a) no b) four c) three d) seven

A: b
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Q: Skin varies in texture, structure and thickness and is made up of ____ components.\Question: Choose the right answer from options given a) three b) seven c) no d) two

A:
a
****