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:
Fawns weigh about ____ to nine pounds at birth.\Question: Choose the right answer from options given a) five b) ten c) nine d) six

Ex Output:
d


Ex Input:
Chlorine has ____ naturally occurring isotopes.\Question: Choose the right answer from options given a) nine b) eight c) three d) two

Ex Output:
d


Ex Input:
Maple syrup is divided into ____ grades.\Question: Choose the right answer from options given a) ten b) seven c) two d) four

Ex Output:

d