Which SDLC phase is primarily concerned with design for systems developed internally?

The correct choice focuses on Phase 3B of the Software Development Life Cycle (SDLC), which is specifically directed towards the detailed design of systems that are developed internally. This phase involves taking the conceptual framework established in earlier phases and creating detailed specifications that include systems architecture, data structures, interfaces, and other component designs necessary for development.

During Phase 3B, the designers work closely with stakeholders to ensure that all functional requirements are effectively transformed into detailed design documents. This meticulous design phase ensures that the system will meet end-user needs and fit appropriately into the overall system architecture. It also helps in identifying potential risks and any organizational constraints that may affect the development process.

This is the stage where clarity on how the system will be built takes precedence, paving the way for the subsequent phase of implementation. Therefore, understanding this distinction is crucial for grasping how the SDLC guides the progress from initial requirements to actual system design, focusing on internal development.