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: Chlorine is manufactured in ____ ways.\Question: Choose the right answer from options given a) four b) two c) nine d) seven

Output: b


Input: Consider Input: Some sources claim there are more like ____ million vertebrate animals in zoos.\Question: Choose the right answer from options given a) six b) five c) one d) three

Output: b


Input: Consider Input: Most dogs start to mature at ____ to three years.\Question: Choose the right answer from options given a) six b) two c) four d) zero


Output: b