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: Harbor porpoises live in groups averaging one to ____ individuals and are very skittish.\Question: Choose the right answer from options given a) seven b) five c) two d) three
Example Output: d

Example Input: Some snails can pull over ____ times their own body-weight.\Question: Choose the right answer from options given a) nine b) six c) five d) three
Example Output: d

Example Input: Starfishes can have at maximum twelve arms and on average ____ arms in total.\Question: Choose the right answer from options given a) no b) five c) nine d) two
Example Output:
b