Final answer:
The bubble symbol can represent either an entity or a process in different types of data flow diagrams, depending on the level of detail presented in the diagram.
Step-by-step explanation:
The symbol that can be either an entity or a process depending on the type of data flow diagram (DFD) is the bubble symbol. In a context-level DFD, the bubble symbol typically represents an entire system or a subsystem, which can be viewed as an entity
However, in a level 1 or level 2 DFD, the bubble symbol represents a specific process within the system. The external entity symbol, data flow symbol, and data store symbol all have specific meanings in DFDs and do not interchange between representing an entity and a process.