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: Women gain ____ years per child they had.\Question: Choose the right answer from options given a) ten b) nine c) four d) two
Example Output: d

Example Input: Calves can browse and follow their mother at three weeks old and are weaned at ____ months.\Question: Choose the right answer from options given a) five b) seven c) four d) three
Example Output: a

Example Input: Safe Heating Keep anything that can burn at least ____ feet away from heaters.\Question: Choose the right answer from options given a) ten b) three c) five d) two
Example Output:
b