MsHumphrey Is Concerned About Brian, a Student in Her High

Ms.Humphrey is concerned about Brian, a student in her high school chemistry class who rarely interacts with other students.Ms.Humphrey decides to smile at Brian on those occasions when she happens to notice him talking with another student.Yet after three weeks she sees little change in his behaviour.Based on this information, which one of the following is definitely wrong with Ms.Humphrey's approach?

A) Brian has little to gain by changing his behaviour.
B) Brian is receiving intermittent rather than continuous reinforcement.
C) Social interaction is not an intrinsically reinforcing activity.
D) A smile is not an effective reinforcer.