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:
Cougars have ____ toes with three distinct lobes present at the base of the pad.\Question: Choose the right answer from options given a) no b) four c) eight d) zero

Ex Output:
b


Ex Input:
Background radiation comes from ____ sources.\Question: Choose the right answer from options given a) zero b) three c) four d) no

Ex Output:
b


Ex Input:
Linen cloth is mentioned in all ____ gospels.\Question: Choose the right answer from options given a) six b) ten c) seven d) four

Ex Output:

d