The main economic problem facing returning war veterans was

Aa shortage of jobs.
Bracial discrimination.
Ca lack of useful work skills.
Dpostwar gloom.

Verified Answer :

The main economic problem facing returning war veterans was "a. a shortage of jobs," since the demand was very high for employment in the US after World War I, and the economy was in a recession. 

Neuron

The main economic problem facing returning war veterans after the Great War also known as World War I was that there was a huge postwar gloom which affected negatively all the people that played a role in it - D.