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: Copper is ____ times higher in dog liver than in human liver.\Question: Choose the right answer from options given a) three b) ten c) six d) one
Example Output: b

Example Input: Ruminants have an even number of toes on each foot and a stomach with either three or ____ chambers.\Question: Choose the right answer from options given a) four b) two c) seven d) five
Example Output: a

Example Input: Women purposely injure themselves three to ____ times more often than men.\Question: Choose the right answer from options given a) two b) four c) one d) nine
Example Output:
b