Which model is described as risk-focused and iterative, with repeated cycles called spirals?

• A. Waterfall
• B. Agile
• C. Spiral
• D. Versioning

Answer: (C)

The concept being tested is a development approach that centers on identifying and addressing risks through repeated cycles. In the Spiral model, work progresses in loops called spirals. Each spiral starts with setting objectives and evaluating risks, then designing and prototyping to mitigate those risks, followed by evaluation and planning for the next spiral. This explicit focus on risk analysis and mitigation at every cycle is what makes it distinct and well-suited for high-risk projects, allowing for incremental refinement as uncertainties are resolved.

Waterfall, by contrast, follows a linear, non-revisiting sequence of phases, so it isn’t driven by ongoing risk assessment. Agile emphasizes iterative delivery and adaptability, but it doesn’t structure each iteration around formal risk analysis in the central way the Spiral model does. Versioning isn’t a lifecycle model at all; it’s about tracking changes to artifacts.