8. Motivating operations can exert stimulus control over a behavior by:

A. Playing a role in the effectiveness of the reinforcer at that point in time
B. Ensuring that the reinforcer is available at that point in time
C. Making reinforcement obsolete at that moment in time
D. Providing prompts that are needed at that moment in time

Motivating operations alter the effectiveness of reinforcers and impact behavior frequency. Discriminative stimuli set the occasion for operant responses, exerting stimulus control.

Explanation:

Motivating operations refer to environmental events that alter the effectiveness of a reinforcer and impact behavior frequency. They can exert stimulus control by affecting the reinforcer's effectiveness at a specific time.

Examples of motivating operations include satiation and deprivation, which change the value of a reinforcer based on the individual's current state.

Discriminative stimuli set the occasion for operant responses without directly eliciting behavior, creating stimulus control over behaviors.

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