At the beginning of "clicker training," I make sure that I always pair two stimuli (a click sound from a hand clicker, and delivery of a fish treat) whenever I provide fish treats to Phoenix, a dolphin in training. This means that I never do a click without following it with the delivery of a fish treat, and Phoenix never gets a fish treat unless it is preceded by a click. This describes an example of a(n):

A) Shaping
B) Chaining
C) Discrimination training
D) Stimulus pairing