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').

Input: Consider 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

Output: d

Input: Consider Input: Most children have a vocabulary of eight to ____ words, including names, by eighteen months of age.\Question: Choose the right answer from options given a) ten b) one c) seven d) eight

Output: a

Input: Consider Input: Seabirds drink seawater that has a salt content ____ times greater than the bird's body fluids.\Question: Choose the right answer from options given a) five b) three c) eight d) four
Output: b