Generate a question which can yield the answer mentioned in the input. Generated question must be answered by the answer provided in input, without using any extra knowledge.
Q: Context : Ross T. Dwyer (July 20, 1919 -- October 8, 2001) was a United States Marine Corps major general who retired in 1974 after over 32 years of service.
Answer : United States Marine Corps
A:
Who did Ross T. Dwyer serve for?