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: Scientists divide bats into ____ groups.\Question: Choose the right answer from options given a) five b) two c) one d) zero

Output: b


Input: Consider Input: Hamsters can live to be three to ____ years old.\Question: Choose the right answer from options given a) four b) two c) three d) nine

Output: a


Input: Consider Input: Oxygen starvation leads to brain cells committing suicide over the following ____ to four days.\Question: Choose the right answer from options given a) three b) eight c) ten d) four


Output: a