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: Gestation lasts ____ months, with the birth of a single calf.\Question: Choose the right answer from options given a) three b) one c) six d) eight

A: d
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Q: Meteorologists rely mainly on ____ types of satellites.\Question: Choose the right answer from options given a) four b) two c) ten d) three

A: b
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Q: Chlorophylls have ____ sub-types, dubbed chlorophyll a, chlorophyll b and chlorophyll c.\Question: Choose the right answer from options given a) four b) zero c) three d) two

A:
c
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