Fixed ratio reinforcement schedule states that reinforcement comes after a fixed number of responses. Which option reflects this?

• A. After a fixed number of responses
• B. After a fixed period of time
• C. After every response
• D. After a varying number of responses

Answer: (A)

Fixed ratio schedules reinforce after a set number of responses. The requirement is constant, so a reward comes only once that exact count has been completed (for example, after every fifth response). Because the number is fixed, the characteristic pattern is bursts of rapid responding followed by a brief pause after each reinforcement, and larger fixed ratios tend to produce longer pauses. This is distinct from reinforcing after a certain amount of time (fixed-interval), reinforcing after every response (continuous reinforcement), or reinforcing after a changing number of responses (variable ratio). So the statement that reflects this is reinforcement after a fixed number of responses.