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:
Most infected persons have ____ symptoms of disease.\Question: Choose the right answer from options given a) six b) no c) three d) one

Ex Output:
b


Ex Input:
Decompression illness is a continuum from ____ symptoms or signs to severe multisystem involvement.\Question: Choose the right answer from options given a) nine b) three c) no d) one

Ex Output:
c


Ex Input:
Spirals have ____ ears to interfere.\Question: Choose the right answer from options given a) three b) no c) nine d) zero

Ex Output:

b