Three-Year-Old Huang Was Classically Conditioned to Salivate to a Bell

Multiple Choice

Three-year-old Huang was classically conditioned to salivate to a bell that was paired with lemon juice. Huang also salivates to the sound of a ringing telephone and to a doorbell, even though they were never used as conditioning stimuli. Huang's salivation to the ringing telephone and to the doorbell illustrate

A) stimulus discrimination.
B) stimulus generalization.
C) extinction.
D) shaping.