What are the kinds of structured nodes? (Choose two)

In UML activity modeling, a structured activity node is an executable activity node that represents a structured portion of an activity graph. It acts as a container for subordinate activity nodes and edges, establishing an isolated context for execution and variable scope. The OMG UML specification defines several concrete subclasses of structured activity nodes to handle specific control flow constructs. Among the given choices, conditional nodes (represented by ConditionalNode) and loop nodes (represented by LoopNode) are official kinds of structured activity nodes. ConditionalNodes execute selected clauses based on evaluation tests, while LoopNodes execute a body clause repeatedly until a test condition fails. Sequence nodes also belong to this category, whereas actions, object nodes, and partitions represent distinct activity concepts.

Option A: Incorrect because a partition (ActivityPartition) is an organizational grouping mechanism for activity nodes, not an executable structured activity node.

Option B: Incorrect because an object node is an abstract activity node used to define object flows, not a structured node container.

Option D: Incorrect because an action is a fundamental executable node, whereas a structured node is a specialized action container holding sub-nodes.

- Object Management Group (OMG). (2015). OMG Unified Modeling Language (OMG UML)

Version 2.5. Section 16.11 (Structured Activity Nodes)

pp. 475-481.

- Object Management Group (OMG). (2015). OMG Unified Modeling Language (OMG UML)

Version 2.5. Section 16.11.4 (ConditionalNode) & Section 16.11.5 (LoopNode)

pp. 478-480.