Which of the following objects are part of BPMN flow objects?

In the context of BPMN (Business Process Model and Notation), flow objects are essential elements that define the behavior and structure of a business process model. Activities are indeed classified as flow objects within BPMN. They represent work that is performed within a process, such as tasks, sub-processes, or call activities. This classification allows for a clear understanding of what happens during a process flow and is crucial when modeling business workflows.

Activities can include various types of tasks, which are specific units of work within a process. Since tasks fall under the broader category of activities, recognizing activities as flow objects allows analysts to effectively design and document business processes in a standardized way.

In contrast, while messages are important in BPMN, serving as a type of communication between process participants, they are not considered flow objects. Stakeholders refer to individuals or groups affected by a process, but they do not constitute flow objects defined in BPMN. Tasks, although they represent a specific type of activity, are not categorized independently as flow objects but rather as a part of the activity classification. Thus, the selection of activities as the correct answer accurately reflects the key components that make up BPMN flow objects.