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: Electrons have almost ____ mass and are negatively charged.\Question: Choose the right answer from options given a) three b) seven c) zero d) no
Example Output: d

Example Input: Interpersonal conflict exists whenever ____ or more people disagree.\Question: Choose the right answer from options given a) five b) seven c) no d) two
Example Output: d

Example Input: Mollusks are the most numerous of the ____ animals.\Question: Choose the right answer from options given a) one b) two c) three d) four
Example Output:
d