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:
Control is defined as a dead plant with ____ signs of life.\Question: Choose the right answer from options given a) ten b) nine c) no d) zero

Ex Output:
c


Ex Input:
Circles mark the approximate locations of ____ recently discovered solar systems.\Question: Choose the right answer from options given a) four b) no c) zero d) nine

Ex Output:
a


Ex Input:
Labor strikes are a ____ sum game.\Question: Choose the right answer from options given a) no b) zero c) seven d) one

Ex Output:

b