Which of the following is a secondary reinforcer?

A) a bar of candy
B) warm, physical contact
C) money
D) a drink of water

A secondary reinforcer is something that doesn't have intrinsic value but has been associated with a primary reinforcer such as food, water or shelter. Money is a secondary reinforcer because it has no intrinsic value but it can be exchanged for primary reinforcers such as food, water or shelter. Choices A, B, and D are primary reinforcers because they have intrinsic value and do not need to be associated with anything else.