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:
Bone marrow replenishes itself fully within ____ weeks.\Question: Choose the right answer from options given a) nine b) no c) one d) two

Ex Output:
d


Ex Input:
Bees possess ____ eyes.\Question: Choose the right answer from options given a) three b) five c) one d) ten

Ex Output:
b


Ex Input:
Perennials live more than ____ years.\Question: Choose the right answer from options given a) one b) nine c) two d) zero

Ex Output:

c