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: Simplify: 250 x 250 - 100 x 100

 Option A: 761200

 Option B: 761400

 Option C: 52500

 Option D: 761500

 Option E: None of them

Output: Option C


Input: Consider Input: Question: There is one highland where planes get fuel. A plan can cover the half of the world with full tank. A plane can transfer fuel from one plane to the other in the air. How many planes are required to make one plane cover the entire world once. Starting point of the travel is the Highland and coming back to the same Highland. All the other planes giving fuels to this Plane should also come back to the same highland and they don't have to cover the entire world.

 Option A: 2

 Option B: 3

 Option C: 4

 Option D: 5

 Option E: 6

Output: Option D


Input: Consider Input: Question: A man said to his son, "I was two-third of your present age when you were born". If the present age of the man is 48 years, find the present age of the son?

 Option A: 25.7 years

 Option B: 28 years

 Option C: 29.3 years

 Option D: 28.8 years

 Option E: 30 years


Output: Option D