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: Urea cycle requires the coordination of ____ different tissues.\Question: Choose the right answer from options given a) two b) four c) nine d) zero

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

A: d
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Q: Carbohydrates contain four calories per gram while fat contains ____ calories per gram.\Question: Choose the right answer from options given a) nine b) four c) three d) five

A:
a
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