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: Vaporization can occur in temperatures as low as ____ degrees.\Question: Choose the right answer from options given a) one b) zero c) eight d) two
Example Output: b

Example Input: Black widows mature in ____ to four months.\Question: Choose the right answer from options given a) two b) seven c) eight d) zero
Example Output: a

Example Input: True glaciers are structurally ____ layered bodies of frozen water.\Question: Choose the right answer from options given a) three b) six c) nine d) no
Example Output:
a