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:
Black bears stand ____ to six feet long and almost three feet at the shoulders when on all fours.\Question: Choose the right answer from options given a) three b) five c) four d) one

Ex Output:
b


Ex Input:
Cows have four stomachs, and the first ____ yield merchantable tripe.\Question: Choose the right answer from options given a) two b) five c) zero d) three

Ex Output:
d


Ex Input:
Northern bettongs live for around ____ years.\Question: Choose the right answer from options given a) five b) six c) four d) zero

Ex Output:

b