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: All of the citizens of a country have a six-character or seven-character national identification code that is created using the 26 letters of the alphabet and the 10 digits from 0 to 9. What is the maximum number of citizens who can be designated with these codes?

 Option A: 36^13

 Option B: 35(36^7

 Option C: 37(36^6

 Option D: 35(36^6

 Option E: 37(36^7
Option C

Question: What is the rate percent when the simple interest on Rs.800 amount to Rs.160 in 4 Years?

 Option A: 5%

 Option B: 6%

 Option C: 2%

 Option D: 95%

 Option E: 1%
Option A

Question: The annual interest rate earned by an investment increased by 10 percent from last year to this year. If the annual interest rate earned by the investment this year was 15 percent, what was the annual interest rate last year?

 Option A: 14.04%

 Option B: 15.04%

 Option C: 13.64%

 Option D: 12.04%

 Option E: 10.04%

Option C