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]: Acoustic guitars come in ____ types.\Question: Choose the right answer from options given a) two b) ten c) one d) four
[EX A]: a

[EX Q]: Today there are ____ major breweries in Mexico that produce a spectrum of tasty beverages.\Question: Choose the right answer from options given a) nine b) six c) zero d) eight
[EX A]: b

[EX Q]: Most male walruses are sexually mature at about eight to ____ years.\Question: Choose the right answer from options given a) ten b) two c) seven d) zero
[EX A]:
a