Which reinforcers are effective due to an organism's biological makeup?

The correct choice is primary reinforcers, which are effective due to an organism's biological makeup. Primary reinforcers are inherently rewarding and fulfill basic biological needs. These include things like food, water, warmth, and shelter, which are essential for survival. Because these reinforcers relate directly to an organism's physiological needs, they are effective in motivating behavior without the need for any trained association or learning process.

Understanding primary reinforcers highlights their importance in learning and behavior modification. For example, when a hungry rat receives food for pressing a lever, the food serves as a primary reinforcer that strengthens the lever-pressing behavior. The biological drives behind these reinforcers make them critical in both natural settings and controlled experimental conditions, distinguishing them from other types of reinforcers that may require learning or conditioning to be effective.