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: Vampires generally are male, and rabies is ____ times more frequent in men than in women.\Question: Choose the right answer from options given a) no b) two c) zero d) seven
Example Output: d

Example Input: Vaccinated newborns have protection for at least ____ years.\Question: Choose the right answer from options given a) four b) five c) two d) no
Example Output: b

Example Input: Mature females bear ____ or even three calves a year.\Question: Choose the right answer from options given a) two b) five c) eight d) ten
Example Output:
a