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: Redwoods reproduce ____ ways.\Question: Choose the right answer from options given a) zero b) two c) six d) nine

A: b
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Q: Avian kidneys have ____ kinds of nephrons.\Question: Choose the right answer from options given a) four b) eight c) no d) two

A: d
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Q: Warthogs also sport ____ sharp tusks.\Question: Choose the right answer from options given a) nine b) one c) four d) zero

A:
c
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