Answer:
They were
A) a flying school for the US Air Force
and
C) a prison for German soldiers
Step-by-step explanation:
In 1942, the government built Camp Gruber, an infantry training camp for the US Army’s 8th Service Command, in Cookson Hills, Oklahoma. It was named in honor of Brigadier General Edmund Gruber, an artillery officer at Fort Sill in Oklahoma. The Manhattan Construction Company put up more than 1,700 buildings in the camp, with facilities that included hospitals and barracks. The company also built the Tulsa Bomber Plant in Tulsa, Oklahoma.
During World War II, about 45,000 soldiers received training at Camp Gruber. The soldiers were from field artillery, infantry, and tank destroyer units. The camp also offered employment to 4,000 civilian workers and held 3,000 German prisoners of war in detention.