Solution

The correct answer is 4) B & D Only.

Key Points

• The Spiral model is a risk-driven process model (Statement B). It focuses on identifying and mitigating risks at each iteration of the model.
• The Spiral model involves a set of anchor point milestones (Statement D) which are used to ensure that the project stays on track and meets its objectives.

Additional Information

• The Spiral model is indeed an incremental process model (Statement A), but that is not the only characteristic; hence, option 4 is more comprehensive.
• The Spiral model is not an acyclic balancing approach (Statement C); it involves repeating cycles, or iterations, to progressively refine the project.
• Each cycle in the Spiral model includes planning, risk analysis, engineering, and evaluation phases.
• The model is particularly effective for large, complex, and high-risk projects where changes are expected during the development process.