A top-down approach to programming calls for: Statement I: Working from the…

Concept

Top-down design, also called stepwise refinement, starts with an overall specification and successively decomposes it into smaller, more detailed modules.

Low-level decisions are deferred until the relevant level of detail, and the decomposition proceeds systematically; writing intermediate code is not part of the design principle itself.

Application

• Statement I follows directly from refinement: an overall problem is broken into increasingly specific parts.

• Statement II follows because details that do not affect the current level are deliberately postponed.

• Statement III follows because each refinement step applies a structured, systematic decomposition.

• Statement IV confuses design refinement with implementation. Top-down design can be expressed in diagrams or pseudocode and does not call for intermediate coding as a defining step.

Contrast

• Statement I only omits the deferred-decision and systematic-refinement characteristics.

• Statements I and II only omit the systematic nature of stepwise refinement.

• Statements I, II and IV replace systematic refinement with intermediate coding.

• Statements I, II and III retain the three design characteristics without adding intermediate coding.

Cross-check

The three retained characteristics all describe design refinement; the excluded statement instead describes coding during implementation.

Result: Statements I, II and III only.