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:
Butterflies have ____ stages in their life cycle.\Question: Choose the right answer from options given a) two b) four c) no d) eight

Ex Output:
b


Ex Input:
Today there are ____ basic classifications of sausage.\Question: Choose the right answer from options given a) five b) four c) six d) one

Ex Output:
a


Ex Input:
Whole crabs are approximately ____ centimeters across.\Question: Choose the right answer from options given a) nine b) ten c) zero d) four

Ex Output:

b