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.
--------
Question: 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

Answer: Option B

Question: Question: The functions f and g are defined for all the positive integers n by the following rule: f(n) is the number of perfect squares less than n and g(n) is the number of primes numbers less than n. If f(x) + g(x) = 16, then x is in the range:

Option A: 30 < x < 36

Option B: 30 < x < 37

Option C: 31 < x < 37

Option D: 31 < x < 38

Option E: 32 < x < 38

Answer: Option C

Question: Question: The time taken by a man to row his boat upstream is twice the time taken by him to row the same distance downstream. If the speed of the boat in still water is 42 kmph, find the speed of the stream?

Option A: 12

Option B: 15

Option C: 14

Option D: 18

Option E: 19

Answer:
Option C