In What Way Do People Sometimes Make Use of an Operant-Conditioning

In what way do people sometimes make use of an operant-conditioning principle when they try to persuade someone to do something?

A) They set up a fixed-interval schedule of punishment.
B) They demonstrate the desired behavior and hope that the other person will imitate it.
C) They reinforce a small amount of cooperation and work up from there.
D) They set up one stimulus and then follow it immediately with another stimulus.