The Central Idea Behind the Concept of Operant Conditioning Is

The central idea behind the concept of operant conditioning is that

A) classical conditioning works best when a single individual does the conditioning.
B) behavior functions parallel to consequences, but is not influenced by them.
C) once a behavior is learned, it can never be truly extinguished.
D) behavior can be encouraged, but it cannot be discouraged.
E) behavior is changed by manipulating its consequences.