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.

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

A: Option D
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Q: Question: If the ratio of a to b is 2 to 3 and the ratio of b to c is 1 to 5, what is the ratio of a to c?

 Option A: 4/15

 Option B: 1/3

 Option C: 2/15

 Option D: 4/5

 Option E: 7/6

A: Option C
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Q: Question: When positive integer X is divided by positive integer Y, the remainder is 5.76. If X/Y = 96.12, what is the value of Y?

 Option A: 96

 Option B: 75

 Option C: 48

 Option D: 25

 Option E: 12

A:
Option C
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