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: Some infected people have ____ symptoms at all.\Question: Choose the right answer from options given a) four b) eight c) no d) five
Example Output: c

Example Input: Most gerbils live three to ____ years and have few health problems.\Question: Choose the right answer from options given a) three b) four c) seven d) zero
Example Output: b

Example Input: American women are four to ____ times more likely than Asian women to die of breast cancer.\Question: Choose the right answer from options given a) nine b) seven c) five d) ten
Example Output:
b