What was the result of the Battle of Stalingrad?
 a. The prolonged battle cost the German army profoundly in troops and equipment and enable a soviet advance
 b. the resolve of the German army led Stalin to agree to a nonaggression pact with Hitler
 c. The German forces held out long enough to end the soviet advance westward
 d/ the starvation of the soviet troops resulted in their defeat and allowed German forces to capture important oil fields