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: 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: Gestation lasts ____ months, with the birth of a single calf.\Question: Choose the right answer from options given a) three b) one c) six d) eight

A: d
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Q: Adaptation is considered to take place in ____ biological and three psychosocial modes.\Question: Choose the right answer from options given a) seven b) no c) five d) one

A:
d
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