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: The original price of a shirt was $20. It was decreased to $15 . What is the percent decrease of the price of this shirt.

 Option A: 25%

 Option B: 35%

 Option C: 45%

 Option D: 55%

 Option E: 65%
[EX A]: Option A

[EX Q]: Question: A sum of Rs. 12500 amounts to Rs. 16000 in 4 years at the rate of simple interest. What is the rate of interest?

 Option A: 7%

 Option B: 5%

 Option C: 6%

 Option D: 8%

 Option E: 14%
[EX A]: Option A

[EX Q]: Question: A woman has 7 daughters and they each have a brother, how many children does she have?

 Option A: 7

 Option B: 8

 Option C: 9

 Option D: 5

 Option E: 3
[EX A]:
Option B