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: Ground beef can last up to four months, and chicken parts can stay good for ____ months.\Question: Choose the right answer from options given a) ten b) no c) nine d) zero
Example Output: c

Example Input: Living cells have at least ____ parts.\Question: Choose the right answer from options given a) seven b) three c) zero d) four
Example Output: b

Example Input: Many lambs are brought to slaughter earlier, however, and often between ____ and eight months of age.\Question: Choose the right answer from options given a) nine b) six c) ten d) eight
Example Output:
b