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: Calves can browse and follow their mother at three weeks old and are weaned at ____ months.\Question: Choose the right answer from options given a) five b) seven c) four d) three

A: a
****
Q: Insects have ____ pairs of legs and three body segments.\Question: Choose the right answer from options given a) one b) nine c) no d) three

A: d
****
Q: Government buildings fly flags of the ____ nations.\Question: Choose the right answer from options given a) ten b) no c) seven d) two

A:
d
****