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: Human females have ____ X chromosomes.\Question: Choose the right answer from options given a) two b) six c) one d) eight

A: a
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Q: Cleavage occurs typically in either one, two, three, four, or ____ directions.\Question: Choose the right answer from options given a) six b) three c) ten d) two

A: a
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Q: Arachnids usually have ____ pairs of walking legs and a specialized pair of feeding appendages.\Question: Choose the right answer from options given a) seven b) five c) four d) nine

A:
c
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