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: Righteousness always points in ____ directions.\Question: Choose the right answer from options given a) six b) two c) one d) four
Example Output: b

Example Input: Earwigs produce ____ or two generations every year.\Question: Choose the right answer from options given a) two b) no c) one d) nine
Example Output: c

Example Input: Older trees are more difficult to train, as bending mature branches can take one to ____ years.\Question: Choose the right answer from options given a) three b) zero c) no d) one
Example Output:
a