instruction:
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: 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
answer:
Option D


question:
Question: How many seconds will a train 100 meters long take to cross a bridge 250 meters long if the speed of the train is 36 kmph?

 Option A: 54 sec

 Option B: 35 sec

 Option C: 25 sec

 Option D: 45 sec

 Option E: 24 sec
answer:
Option B


question:
Question: A card from a pack of 52 cards is lost. From the remaining cards of the pack, two cards are drawn and are found to be both spade. Find the probability of the lost card being a spade.

 Option A: 10/50

 Option B: 10/53

 Option C: 11/50

 Option D: 11/53

 Option E: 12/53
answer:

Option C