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:
Calves can swim ____ days after they are born.\Question: Choose the right answer from options given a) ten b) two c) zero d) one

Ex Output:
b


Ex Input:
Corn borers complete at least ____ generations each summer.\Question: Choose the right answer from options given a) zero b) three c) two d) ten

Ex Output:
c


Ex Input:
Compound semiconductors are made of ____ or more elements.\Question: Choose the right answer from options given a) two b) four c) five d) one

Ex Output:

a