Q: Given a math problem with context and a question and 5 answer choices, the task is to provide the correct answer choice based on the problem. You must choose one of the given answer choices by letter: a, b, c, d, or e; anything else is invalid.
Problem: jo ' s collection contains us, indian and british stamps. if the ratio of us to indian stamps is 5 to 2 and the ratio of indian to british stamps is 5 to 1, what is the ratio of us to british stamps ?
Options: a. 10: 5, b. 15: 2, c. 20: 2, d. 25: 2, e. none of these
A:
d