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 Input:
Most volcanoes erupt for ____ to four weeks and then rest.\Question: Choose the right answer from options given a) three b) four c) one d) eight

Ex Output:
a


Ex Input:
Trappers have ____ genders and reproduce sexually.\Question: Choose the right answer from options given a) zero b) two c) five d) one

Ex Output:
b


Ex Input:
Bats sleep all day and some of the night, and some hibernate for eight or ____ months of the year.\Question: Choose the right answer from options given a) six b) nine c) no d) one

Ex Output:

b