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: Acoustic guitars come in ____ types.\Question: Choose the right answer from options given a) two b) ten c) one d) four

Output: a


Input: Consider Input: Natural chlorine contains ____ isotopes.\Question: Choose the right answer from options given a) two b) six c) eight d) seven

Output: a


Input: Consider Input: Alcohol reduces the brain's ability to integrate information from the ____ senses.\Question: Choose the right answer from options given a) five b) eight c) two d) six


Output: a