In the COM-B model, which components interact to produce behavior?

• A. Attitude, Norms, and Control
• B. Knowledge, Skills, and Abilities
• C. Environment, Reinforcement, and Cue
• D. Capability, Opportunity, and Motivation

Answer: (D)

Behavior in the COM-B model comes from the interaction of three elements: Capability, Opportunity, and Motivation. Capability means having the knowledge and skills to perform the behavior. Opportunity covers the external factors that make the behavior possible, such as the environment, resources, and social support. Motivation includes the desires and driving forces that propel action, both reflective (conscious intentions) and automatic (habits, impulses).

These three components work together, so you need all of them to produce behavior. If any one is lacking, the behavior is unlikely: you might have the skills and desire, but no opportunity; or you might have opportunity and skills but lack motivation; or you might be motivated but lack the necessary capability or the enabling environment.

The other options mix terms from different theories or omit key elements. Attitude, norms, and perceived control resemble constructs from other behavior theories; knowledge, skills, and abilities focus mainly on capability; and environment, reinforcement, and cue miss the essential role of motivation and the full scope of capability and opportunity.