Definition: 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.
Input: Question: Three numbers are in the ratio 3:5:7. The largest number is 56. What is the difference between smallest and largest number?

 Option A: 20

 Option B: 24

 Option C: 28

 Option D: 32

 Option E: 36

Option D