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: 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
[EX A]: Option C

[EX Q]: Question: A warehouse is labeling computer inventory with 3-digit codes. Each code is to consist of four digits between the numbers 0 and 9. The manager is debating whether to allow any 3-digit codes to have leading zero's before a non-zero number is used. If not allowed, then numbers like0025cannot be used.
The manager wants to measure the magnitude of the number of 3-digit code possibilities that are lost if he disallows the use of leading zero's. How many such codes would be lost?

 Option A: 981

 Option B: 1000

 Option C: 1011

 Option D: 1101

 Option E: 100
[EX A]: Option E

[EX Q]: Question: What is the square root of 169?

 Option A: 8

 Option B: 16

 Option C: 13

 Option D: 42

 Option E: 25
[EX A]:
Option C