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: Cows can be up to ____ times more active than normal while in heat.\Question: Choose the right answer from options given a) eight b) nine c) two d) six
Example Output: a

Example Input: Water is present in all ____ phases in Earth s atmosphere.\Question: Choose the right answer from options given a) six b) nine c) two d) three
Example Output: d

Example Input: Ticks begin as eggs and hatch into the ____ legged larval form.\Question: Choose the right answer from options given a) one b) six c) three d) two
Example Output:
b