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: Pupae usually transform into adults ____ to three days later.\Question: Choose the right answer from options given a) one b) two c) no d) eight

Answer: b


Question: Healthcare providers diagnose ____ general types of insomnia.\Question: Choose the right answer from options given a) two b) eight c) one d) three

Answer: a


Question: Some couples have ____ obvious explanation for their infertility.\Question: Choose the right answer from options given a) no b) nine c) five d) zero

Answer:
a