The primary tool used in structured design is a:Select one:a.structure chartb.data-flow diagramc.program flowchartd.modulee.None of the above

Sure, let's analyze each option step by step to determine the correct answer.

a. Structure Chart: A structure chart is a hierarchical diagram that shows the breakdown of a system into its component modules. It is used in structured design to represent the architecture of a system.

b. Data-Flow Diagram (DFD): A data-flow diagram is used to represent the flow of data within a system. It shows how data moves from input to output through various processes.

c. Program Flowchart: A program flowchart is a graphical representation of the sequence of operations in a program. It is used to visualize the logic and flow of a program.

d. Module: A module is a self-contained unit of code that performs a specific function. While modules are important in structured design, they are not a tool used to represent the design.

e. None of the above: This option suggests that none of the provided answers are correct.

Given the context of structured design, the primary tool used is the Structure Chart. This is because structure charts are specifically designed to represent the hierarchical organization of a system's components, which is a key aspect of structured design.

Therefore, the correct answer is:

a. Structure Chart