A use case diagram is a ______ _______ view of the system.

A use case diagram is a ______ _______ view of the system.

• A. White box
• B. Black box
• C. Grey box
• D. Glass box

Answer: (B)

Use case diagrams present the system from an external perspective, focusing on what the system does for actors rather than how it does it. This makes them a black box view, since the internal structure, logic, and implementation details are hidden while you see the interactions and available services. White box or glass box would expose internal components and code, which use case diagrams intentionally do not show. Grey box implies partial internal knowledge, which isn’t what a use case diagram conveys. For example, you’d see a use case like "Process payment" with the actor and system interactions, but not the internal payment processing steps.

Use case diagrams present the system from an external perspective, focusing on what the system does for actors rather than how it does it. This makes them a black box view, since the internal structure, logic, and implementation details are hidden while you see the interactions and available services. White box or glass box would expose internal components and code, which use case diagrams intentionally do not show. Grey box implies partial internal knowledge, which isn’t what a use case diagram conveys. For example, you’d see a use case like "Process payment" with the actor and system interactions, but not the internal payment processing steps.