In the context of system analysis, which of the following best defines the "use case" diagram?

A use case diagram is a vital tool in system analysis that illustrates how various actors (users or external systems) interact with the system to accomplish specific goals. It focuses on functional requirements, ensuring that all user interactions are captured effectively. Key components of a use case diagram include:

• Actors : Entities interacting with the system, such as users or external systems.
• Use Cases : Functionalities or actions performed by the system to meet user goals.
• Relationships : Depictions of interactions, such as associations, dependencies, and generalizations.

For example, in an online shopping system, a use case diagram might include actors like "Customer" and "Admin," with use cases such as "Browse Products," "Add to Cart," and "Manage Inventory." Explanation of Incorrect Options: A) A visual representation of how data flows within the system : This describes a data flow diagram (DFD), not a use case diagram. B) A diagram depicting the physical layout of the system’s components : This refers to a physical architecture diagram, unrelated to use cases. D) A hierarchical chart showing system modules and their relationships : This describes a module or component diagram, not a use case diagram. E) A flowchart illustrating step-by-step processes within the system : Flowcharts detail sequential workflows but do not represent actor-system interactions.