In MDC3, what is an architecture decision record (ADR) and its purpose?

• A. An ADR outlines the project budget and milestones.
• B. An ADR describes user interface style guides.
• C. An ADR documents architectural decisions, rationale, alternatives considered, and status for future reference in MDC3.
• D. An ADR lists test cases.

Answer: (C)

An architecture decision record is a lightweight document that captures a real architectural choice, why it was made, what alternatives were considered, and the current status of that decision. In MDC3, its purpose is to provide a clear, lasting reference for future developers: it documents the decision, the reasoning behind it, the trade-offs evaluated, and where things stand today so someone can understand the context without digging through old discussions. This helps with onboarding, maintaining consistency as the system evolves, and re-evaluating choices if requirements or technologies change.

This isn’t about project budgets and milestones, UI style guides, or test cases—the ADR focuses on architectural decisions and their rationale, not managerial, design, or verification artifacts.