Which of the following elements of a use case diagram is used to indicate those...

A use case diagram is a visual representation of how users (or systems) interact with a system to achieve specific goals. Actors represent the entities (e.g., users or external systems) that expect to receive services from the system.

Key Elements of a Use Case Diagram:

Actors: Represent individuals or systems that interact with the system to achieve a goal.

System Boundaries: Define the scope of the system being modeled.

Users: While " users " may seem similar to actors, the term " actors " is the correct technical term in use case diagrams.

Entities: Entities typically refer to data objects or components, not those receiving services.

Evaluation of Each Option:

A. Actors: Actors are the correct element used to indicate those who expect to receive a service from the system. Conclusion: This is correct .

B. System boundaries: System boundaries define the scope of the system but do not represent those receiving services. Conclusion: This is not correct .

C. Users: While users may interact with the system, the correct term in use case diagrams is " actors. " Conclusion: This is not correct .

D. Entities: Entities represent data objects or components, not those receiving services. Conclusion: This is not correct .