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]: Cows breed at ____ years, bulls at four.\Question: Choose the right answer from options given a) two b) three c) seven d) one
[EX A]: b

[EX Q]: Banks hold ____ excess reserves and the public holds no currency.\Question: Choose the right answer from options given a) two b) seven c) ten d) no
[EX A]: d

[EX Q]: Plants stand one to ____ feet tall.\Question: Choose the right answer from options given a) seven b) no c) six d) two
[EX A]:
d