In the Learned Helplessness Experiments, Dogs Learned to Passively Submit

In the learned helplessness experiments, dogs learned to passively submit to shocks by the experimenters

A) flashing a signal light before each shock so the dog freezes with fear.
B) forcibly dragging the dog to the shock department.
C) administering several shocks while preventing escape.
D) placing a barrier so the dog must leap to escape the shocks.