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: Babies show an interest in solid foods when they are approximately four to ____ weeks old.\Question: Choose the right answer from options given a) nine b) eight c) five d) six

A: c
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Q: Young emus are very vulnerable to disease until they are about ____ months old.\Question: Choose the right answer from options given a) no b) ten c) six d) three

A: d
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Q: Water consists of ____ hydrogen and one oxygen atom.\Question: Choose the right answer from options given a) five b) nine c) three d) two

A:
d
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