You Are Waiting at the Crosswalk for the Light to Change

Multiple Choice

You are waiting at the crosswalk for the light to change. Finally the "WALK" sign illuminates and you begin to cross the street. Even though you watch for traffic as you cross, you have learned that the appearance of this light usually means that it is safe to cross the street. Thus, the "WALK" sign would be considered an example of a

A) discriminative stimulus
B) response cost
C) negative reinforcer
D) positive reinforcer