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').

Input: Consider Input: Ozone is a molecule containing ____ oxygen atoms.\Question: Choose the right answer from options given a) one b) nine c) no d) three

Output: d


Input: Consider Input: Some taxonomists classify only ____ species though.\Question: Choose the right answer from options given a) one b) six c) two d) three

Output: c


Input: Consider Input: Most couples expect to get pregnant within about ____ months of trying.\Question: Choose the right answer from options given a) six b) two c) five d) ten


Output: a