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: Nightmares happen frequently in childhood, especially between the ages of ____ and six.\Question: Choose the right answer from options given a) three b) eight c) no d) ten

A: a
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Q: Dunes are of ____ types - linear and parabolic.\Question: Choose the right answer from options given a) three b) four c) ten d) two

A: d
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Q: Trilobites have a segmented body that is divided by into ____ vertical lobes.\Question: Choose the right answer from options given a) six b) no c) three d) nine

A:
c
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