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: 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: Some people try to count to ____ when they feel angry.\Question: Choose the right answer from options given a) no b) ten c) seven d) five

Output: b


Input: Consider Input: Cleavage is good in ____ directions at right angles.\Question: Choose the right answer from options given a) eight b) two c) one d) six


Output: b