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: Litters contain from one to ____ kittens, and tend to be much larger when prey is abundant.\Question: Choose the right answer from options given a) three b) four c) two d) seven
Example Output: b

Example Input: All baleen whales have ____ blow holes.\Question: Choose the right answer from options given a) zero b) four c) seven d) two
Example Output: d

Example Input: Spiders are different from insects, spiders have eight legs and insect only have ____ legs.\Question: Choose the right answer from options given a) five b) eight c) four d) six
Example Output:
d