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: The average age of 31 students in a group is 16 years. when teacher's age is included to it, the average increases by one.What is the teacher's age in years?

 Option A: 31

 Option B: 36

 Option C: 48

 Option D: 45

 Option E: 57

Output: Option C


Input: Consider Input: Question: Bat is bought for Rs.400 and sold at a gain of 20% find its selling price?

 Option A: Rs.320

 Option B: Rs.350

 Option C: Rs.370

 Option D: Rs.480

 Option E: None of these

Output: Option D


Input: Consider Input: Question: The factorial expression 9!/2! is not divisible by which of the following integers?

 Option A: 3

 Option B: 2

 Option C: 6

 Option D: 7

 Option E: 11


Output: Option E