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 Q]: Question: A sum of Rs.4800 is invested at a compound interest for three years, the rate of interest being 10% p.a., 20% p.a. and 25% p.a. for the 1st, 2nd and the 3rd years respectively. Find the interest received at the end of the three years?

 Option A: Rs.3129

 Option B: Rs.3120

 Option C: Rs.3108

 Option D: Rs.3106

 Option E: Rs.3127
[EX A]: Option B

[EX Q]: Question: What sum of money will produce Rs.70 as simple interest in 4 years at 3 1/2 percent?

 Option A: 266

 Option B: 500

 Option C: 287

 Option D: 26

 Option E: 281
[EX A]: Option B

[EX Q]: Question: In N is a positive integer less than 200, and 14N/60 is an integer, then N has how many different positive prime factors R?

 Option A: 2

 Option B: 3

 Option C: 5

 Option D: 6

 Option E: 8
[EX A]:
Option B