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: Corn borers complete at least ____ generations each summer.\Question: Choose the right answer from options given a) zero b) three c) two d) ten
Example Output: c

Example Input: Sound waves travel through the air in a similar manner, but in all ____ dimensions.\Question: Choose the right answer from options given a) three b) five c) nine d) one
Example Output: a

Example Input: Chemicals generally form ____ kinds of hazards, physical and health.\Question: Choose the right answer from options given a) three b) two c) no d) five
Example Output:
b