The Hull-Spence model computes prediction error as the difference between:
A) the expectation of the unconditioned stimulus (US) generated only by the conditioned stimulus (CS) whose associative strength is being updated and the expectation of the US generated by all the CSs that are presented on that trial
B) the experienced unconditioned stimulus (US) and the expectation of the US generated only by the conditioned stimulus (CS) whose associative strength is being updated
C) the experienced unconditioned stimulus (US) and the expectation of the US generated by all the conditioned stimuli that the animal has had experience with
D) the experienced unconditioned stimulus (US) and the expectation of the US generated by all the conditioned stimuli that are presented on that trial.