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').
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Question: Elephants give birth to ____ calf every four to nine years on average.\Question: Choose the right answer from options given a) ten b) one c) eight d) six

Answer: b


Question: Astronauts sleep only ____ hours each night, on average.\Question: Choose the right answer from options given a) six b) one c) four d) seven

Answer: a


Question: Most tanagers live in pairs or in small groups of three to ____ individuals.\Question: Choose the right answer from options given a) zero b) nine c) eight d) five

Answer:
d