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: Manatees swim two to ____ miles per hour.\Question: Choose the right answer from options given a) no b) six c) five d) zero
Example Output: b

Example Input: Embrasures have ____ functions.\Question: Choose the right answer from options given a) three b) seven c) zero d) nine
Example Output: a

Example Input: Single lambs weigh about ____ pounds, twins, four to five pounds.\Question: Choose the right answer from options given a) eight b) nine c) four d) seven
Example Output:
a