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').

[EX Q]: Real airplanes have round engines and ____ wings.\Question: Choose the right answer from options given a) four b) six c) three d) two
[EX A]: d

[EX Q]: Mammals have only ____ sets of teeth.\Question: Choose the right answer from options given a) six b) five c) seven d) two
[EX A]: d

[EX Q]: Moles are about the size of chipmunks and can weigh anywhere from ____ to six ounces.\Question: Choose the right answer from options given a) one b) three c) four d) no
[EX A]:
b