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: Females have two X-chromosomes, ____ from each parent.\Question: Choose the right answer from options given a) ten b) four c) one d) zero
Example Output: c

Example Input: Vision disorders affect one in every ____ school-age children.\Question: Choose the right answer from options given a) five b) four c) nine d) one
Example Output: b

Example Input: Destructive power plays ____ main roles in society.\Question: Choose the right answer from options given a) ten b) eight c) two d) three
Example Output:
c