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.

Ex Input:
Question: If x, y, and z are positive integers such that x is a factor of y and y is a factor of z, which of the following is NOT necessarily an integer?

 Option A: (x + y

 Option B: (y + z

 Option C: yz/x

 Option D: (2y + 3z

 Option E: (xy + z

Ex Output:
Option A


Ex Input:
Question: Running at the same constant rate, 8 identical machines can produce a total of 240 pens per minute. At this rate, how many pens could 5 such machines produce in 5 minutes?

 Option A:  114

 Option B:  108

 Option C:  192

 Option D:  750

 Option E:  777

Ex Output:
Option D


Ex Input:
Question: A certain quantity of 45% concentration solution is replaced with 15% concentration solution such that the concentration of the combined amount is 35%.
What's the ratio of the amount of solution that was replaced to the amount of solution that was not replaced?

 Option A: 1:3

 Option B: 1:2

 Option C: 2:3

 Option D: 2:1

 Option E: 3:1

Ex Output:

Option B