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: Grasshoppers are ____ inches long and can knock a man off a bicycle.\Question: Choose the right answer from options given a) six b) ten c) four d) eight
Example Output: a

Example Input: Plants can uptake ____ times more nutrients, and improve soil texture at the same time.\Question: Choose the right answer from options given a) no b) two c) three d) ten
Example Output: d

Example Input: Monarchs have a life span of seven to ____ months.\Question: Choose the right answer from options given a) eight b) four c) three d) six
Example Output:
a