In an activity diagram, which token indicates which action is currently enabled during execution?

In an activity diagram, which token indicates which action is currently enabled during execution?

• A. Object token
• B. Control token
• C. Data token
• D. Event token

Answer: (B)

In an activity diagram, tokens show how execution flows along the control paths. The token that marks which action is currently enabled is the control token. It travels along a control flow into an action, and when it arrives, that action is ready to fire. After the action executes, the control token moves on to enable the next step. Other tokens carry data or objects produced or consumed by actions (data tokens and object tokens), and they don’t indicate which action is currently enabled. Event tokens aren’t the standard mechanism for showing enabling in these diagrams.

In an activity diagram, tokens show how execution flows along the control paths. The token that marks which action is currently enabled is the control token. It travels along a control flow into an action, and when it arrives, that action is ready to fire. After the action executes, the control token moves on to enable the next step. Other tokens carry data or objects produced or consumed by actions (data tokens and object tokens), and they don’t indicate which action is currently enabled. Event tokens aren’t the standard mechanism for showing enabling in these diagrams.