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: Rahul went to a shop and bought things worth Rs. 50, out of which 80 Paise went on sales tax on taxable purchases. If the tax rate was 8%, then what was the cost of the tax free items?

Option A: 21.4

Option B: 12.4

Option C: 41.2

Option D: 39.2

Option E: 32.9

Output: Option D

Input: Consider Input: Question: In how many seconds will a train 100 meters long pass an oak tree, if the speed of the train is 36 km/hr?

Option A: 6

Option B: 8

Option C: 10

Option D: 12

Option E: 14

Output: Option C

Input: Consider Input: Question: A train moves fast a telegraph post and a bridge 264 m long in 8 sec and 20 sec respectively. What is the speed of the train?

Option A: 4

Option B: 6

Option C: 7

Option D: 8

Option E: 2
Output: Option C