Difficulty: Medium
Correct Answer: Flow chart (used as a process specification, i.e., mini-spec/PSPEC)
Explanation:
Introduction: A data-flow diagram deliberately hides internal algorithmic detail. To capture what happens inside a process bubble, analysts attach a separate process specification (PSPEC), which may be documented by a flow chart, decision table, or structured English.
Given Data / Assumptions:
Concept / Approach: Keep DFDs simple and focused on data movement. When detail is needed, use a PSPEC. A flow chart is a well-known format to express activities and decisions step by step, which suits process internals.
Step-by-Step Solution: 1) Identify the missing layer: internal logic of a DFD process. 2) Choose a suitable PSPEC form that captures activities and decisions. 3) Flow chart is a standard choice to specify methods and procedures.
Verification / Alternative check: Methodologies (e.g., Yourdon/DeMarco) explicitly recommend a PSPEC alongside DFDs. Flow charts, decision tables, and structured English are typical options.
Why Other Options Are Wrong: Option A: “Datagram” is not a DFD documentation artifact in this context. Option B: “Actigram” is not a standard DFD attachment. Option C: Feedback is a control concept, not a full specification artifact. Option E: Incorrect because flow charts are accepted PSPECs.
Common Pitfalls: Trying to cram algorithmic detail directly into the DFD. The DFD should remain readable; use a PSPEC artifact such as a flow chart for internal logic.
Final Answer: Flow chart (used as a process specification, i.e., mini-spec/PSPEC)
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