In an extend relationship, the extending use case is located at which end?

In an extend relationship, the extending use case is located at which end?

• A. tail end
• B. head end
• C. middle end
• D. end end

Answer: (A)

In UML use-case diagrams, an extend relationship models optional or conditional behavior added to a base use case by another use case. The extending use case provides the extra steps and is connected to the base use case via a dashed line that points toward the base use case. This orientation shows that the base use case is the one being extended, while the extending use case is attached at the far end of the relationship—the tail end. The extension points are defined inside the base use case, indicating where the extending use case can inject its behavior when certain conditions are met. So the extending use case sits at the tail end.

In UML use-case diagrams, an extend relationship models optional or conditional behavior added to a base use case by another use case. The extending use case provides the extra steps and is connected to the base use case via a dashed line that points toward the base use case. This orientation shows that the base use case is the one being extended, while the extending use case is attached at the far end of the relationship—the tail end. The extension points are defined inside the base use case, indicating where the extending use case can inject its behavior when certain conditions are met. So the extending use case sits at the tail end.