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: Big bluestem grows up to ____ feet tall.\Question: Choose the right answer from options given a) seven b) no c) nine d) eight

A: c
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Q: Water weighs about ____ pounds per gallon.\Question: Choose the right answer from options given a) seven b) ten c) zero d) nine

A: b
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Q: Ferrets usually reach full adult size by the age of ____ months.\Question: Choose the right answer from options given a) six b) four c) ten d) eight

A:
a
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