You are given a math word problem and you are supposed to make use of mathematical concepts like probability, combinatorics, linear equations, sequences/series, or simple operators like addition, subtraction, division, or multiplication to answer the given question. Choose the best option from the 5 given options and report that option.

Input: Consider Input: Question: x% of y is y% of ?

 Option A: x

 Option B: 100x

 Option C: x/100

 Option D: y/100

 Option E: None

Output: Option A


Input: Consider Input: Question: Which of the following CANNOT be weighed using a balance scale and these unit weights: 1, 4, 7, and 10

 Option A: 13

 Option B: 15

 Option C: 17

 Option D: 19

 Option E: 21

Output: Option A


Input: Consider Input: Question: A and B can do a piece of work in 45 days and 40 days respectively. They began to do the work together but A leaves after some days and then B completed the remaining work in 23 days. The number of days after which A left the work was

 Option A: 5 days

 Option B: 6 days

 Option C: 7 days

 Option D: 9 days

 Option E: 8 days


Output: Option D