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:
All birds have ____ legs with four toes each.\Question: Choose the right answer from options given a) zero b) one c) three d) two

Ex Output:
d


Ex Input:
Some infected horses show ____ signs and become chronic carriers of the disease.\Question: Choose the right answer from options given a) nine b) six c) four d) no

Ex Output:
d


Ex Input:
Studies show that childhood obesity is epidemic and that one in ____ children is overweight.\Question: Choose the right answer from options given a) five b) six c) nine d) ten

Ex Output:

a