In programming, which design approach begins with high-level modules and decomposes into smaller parts?

In programming, which design approach begins with high-level modules and decomposes into smaller parts?

• A. Top-down
• B. Bottom-up
• C. Modular
• D. Iterative

Answer: (A)

Starting with a high-level view of the system and breaking it down into smaller parts is top-down design. The approach emphasizes outlining the major modules and their responsibilities first, then progressively refining each module into submodules and concrete implementations. This stepwise refinement helps manage complexity by establishing clear interfaces and architecture before diving into details. For example, when designing a library system, you’d first define broad components like Catalog, User Management, Lending, and Reporting, then decompose each into smaller parts such as Catalog/Search, Database Access, and UI. This aligns with the idea of decomposing a big problem into manageable pieces, which is why top-down is the best fit. Bottom-up focuses on building from small components upward, iterative emphasizes development cycles, and modular refers to organizing code into modules rather than the starting approach.

Starting with a high-level view of the system and breaking it down into smaller parts is top-down design. The approach emphasizes outlining the major modules and their responsibilities first, then progressively refining each module into submodules and concrete implementations. This stepwise refinement helps manage complexity by establishing clear interfaces and architecture before diving into details. For example, when designing a library system, you’d first define broad components like Catalog, User Management, Lending, and Reporting, then decompose each into smaller parts such as Catalog/Search, Database Access, and UI. This aligns with the idea of decomposing a big problem into manageable pieces, which is why top-down is the best fit. Bottom-up focuses on building from small components upward, iterative emphasizes development cycles, and modular refers to organizing code into modules rather than the starting approach.