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]: Many tractors have ____ wheel drive to get extra grip on the hills and in wet conditions.\Question: Choose the right answer from options given a) four b) seven c) five d) two
[A]: a

[Q]: Asthma accounts for ____ in six of all pediatric emergency visits in the United States.\Question: Choose the right answer from options given a) four b) seven c) one d) six
[A]: c

[Q]: Embryonal cell divides and form ____ celled octant.\Question: Choose the right answer from options given a) six b) eight c) no d) one
[A]:
b