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:
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:
Today there are ____ UK hospitals doing heart transplants.\Question: Choose the right answer from options given a) three b) five c) six d) nine

Ex Output:
d


Ex Input:
Most people buy a new car every three to ____ years depending on their income and needs.\Question: Choose the right answer from options given a) nine b) seven c) three d) ten

Ex Output:

d