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').

Example Input: Babies are breast-fed until about ____ years of age.\Question: Choose the right answer from options given a) four b) nine c) eight d) two
Example Output: d

Example Input: Most people have ____ kidneys.\Question: Choose the right answer from options given a) two b) five c) seven d) six
Example Output: a

Example Input: Quadrature is a ____ player strategy game.\Question: Choose the right answer from options given a) zero b) eight c) three d) two
Example Output:
d