Answer:
A)Korean war
Step-by-step explanation:
the Korean war started in 1950 and ended in 1953. world war 1 started in 1914 and ended in 1918. the Vietnam war started in 1955 and ended is 1975. world war 2 started in 1939 and ended in 1945. since the Korean war started in 1950 it is very likely that military spending increased because of the Korean war and not any of the other wars that were mentioned.