A _____ fulfills a basic need like hunger.

• A. secondary reinforcer
• B. punishment by removal
• C. discriminative stimulus
• D. primary reinforcer

Answer: (D)

Verified step by step guidance

1. Understand the concept of 'primary reinforcer': A primary reinforcer is something that fulfills a basic biological need, such as food, water, or sleep. These are naturally reinforcing because they are essential for survival.
2. Differentiate between primary and secondary reinforcers: Secondary reinforcers are learned and acquire their reinforcing properties through association with primary reinforcers. Examples include money or praise.
3. Consider the options provided: Analyze each option to determine which one aligns with the definition of a primary reinforcer.
4. Evaluate 'secondary reinforcer': Recognize that secondary reinforcers do not fulfill basic needs directly but are linked to primary reinforcers.
5. Conclude with the correct choice: Identify 'primary reinforcer' as the correct answer since it directly fulfills a basic need like hunger.