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: Some infected horses show ____ signs and become chronic carriers of the disease.\Question: Choose the right answer from options given a) nine b) six c) four d) no

A: d
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Q: Control is defined as a dead plant with ____ signs of life.\Question: Choose the right answer from options given a) ten b) nine c) no d) zero

A: c
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Q: Breast milk is the only food recommended for the first four to ____ months of an infant's life.\Question: Choose the right answer from options given a) one b) nine c) seven d) six

A:
d
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