You train hungry rats that a conditioned stimulus (CS) predicts delivery of an unconditioned stimulus (US). Which of the following procedures is most likely to produce the strongest goal-tracking conditional response (CR)? Group of answer choices CS= tone, US= 1 mA footshock, CS-US interval 4 seconds, inter-trial interval 100 seconds CS= tone, US= 1 food pellet, CS-US interval 10 seconds, inter-trial interval 100 seconds CS= light, US= 3 food pellet, CS-US interval 4 seconds, inter-trial interval 20 seconds CS= tone, US = 3 food pellets, CS-US interval 2 seconds, inter-trial interval 20 seconds CS= light, US= 3 food pellets, CS-US interval 5 seconds, inter-trial interval 50 seconds