In a UML process model, how is a task represented?

In a UML (Unified Modeling Language) process model, a task is represented by a round-cornered rectangle. This geometric shape is a standard notation in UML, specifically used to denote activities or tasks within a process. The description of the task is typically expressed as a verb-noun phrase, which clearly communicates the action being performed and the object of that action. For example, a task could be titled "Approve Purchase Order," where "Approve" is the verb and "Purchase Order" is the noun. This concise representation enhances clarity within a process model.

The other options, while relevant to process modeling, do not specifically describe how a task is represented within a UML context. While tasks can indeed be performed by one person or involve validation by actors, these characteristics are not intrinsic to their depiction in UML, which focuses on the visual representation and naming conventions instead. Similarly, the identification of tasks often involves observations and meetings, but this pertains to the identification process rather than their representation in the model itself. Thus, the emphasis on the round-cornered rectangle as a visual symbol and its noun-verb naming convention is what makes this answer accurate.