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: Oranges signify good health, and the number ____ sounds like the word for prosperity.\Question: Choose the right answer from options given a) eight b) ten c) seven d) five

A: a
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Q: Female elephants have babies about ____ years apart, and they have only one each time.\Question: Choose the right answer from options given a) eight b) one c) zero d) three

A: d
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Q: Ferrets have ____ to four hour digestive tracts.\Question: Choose the right answer from options given a) three b) one c) ten d) six

A:
a
****