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:
Many aneurysms have ____ symptoms until they burst.\Question: Choose the right answer from options given a) no b) five c) six d) seven

Ex Output:
a


Ex Input:
Digital bandwidth enables signal to be condensed as a five to ____ ratio.\Question: Choose the right answer from options given a) one b) nine c) seven d) six

Ex Output:
a


Ex Input:
Snails can sleep for ____ years without eating.\Question: Choose the right answer from options given a) ten b) three c) zero d) nine

Ex Output:

b