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 value of 3Z + Z(ZZ)(ZZ) when Z = 5 is:

 Option A: 3150

 Option B: 3200

 Option C: 3140

 Option D: 3650

 Option E: 3104
[EX A]: Option C

[EX Q]: Question: The greatest common factor of 16 and the positive integer n is 4, and the greatest common factor of n and 45 is 3. Which of the following could be the greatest common factor of n and 210?

 Option A: 3

 Option B: 14

 Option C: 30

 Option D: 42

 Option E: 70
[EX A]: Option D

[EX Q]: Question: he two trains of lengths 400 m, 600 m respectively, running at same directions. The faster train can cross the slower train in 180 sec, the speed of the slower train is 48 km. then find the speed of the faster train?

 Option A: 76 Kmph

 Option B: 68 Kmph

 Option C: 87 Kmph

 Option D: 56 Kmph

 Option E: 10 Kmph
[EX A]:
Option B