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: Bacteria come in ____ basic shapes.\Question: Choose the right answer from options given a) five b) one c) three d) nine
Example Output: c

Example Input: Female cats can go into heat for the first time as early as ____ months of age.\Question: Choose the right answer from options given a) four b) zero c) five d) eight
Example Output: c

Example Input: Elliptical galaxies are probably a mix of all ____ shapes.\Question: Choose the right answer from options given a) seven b) three c) two d) four
Example Output:
b