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').

Input: Consider Input: Wolverines reproduce every ____ or three years.\Question: Choose the right answer from options given a) two b) three c) one d) four

Output: a


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

Output: a


Input: Consider Input: Walkers move around, sometimes alone and sometimes in groups of ____ or more.\Question: Choose the right answer from options given a) five b) nine c) ten d) no


Output: a