Answer:
d. responding similarly to a range of similar stimuli
Step-by-step explanation:
Stimulus generalization: In psychology, the term stimulus generalization is a part of the classical conditioning theory which was given by Ivan Pavlov.
Stimulus generalization refers to the propensity of a conditioned stimulus to produce the same response once the response has been conditioned. This is one of the learning processes that can also occur in operant conditioning to evoke a similar response once a particular response in being conditioned in the past.
In the question above, generalization refers to responding similarly to a range of similar stimuli.