According to the BABOK® Guide, a waterfall approach is a sequential project life cycle that consists of distinct phases, such as initiation, planning, analysis, design, construction, testing, implementation, and maintenance. Each phase has a defined set of activities, deliverables, and exit criteria that must be completed before moving to the next phase. A waterfall approach is suitable for projects that have a clear and stable scope, well-defined requirements, and minimal changes or uncertainty. In this scenario, a new contract requires a thorough level of documentation to be developed and maintained with planned phases of reviews and authorized sign offs. This implies that the project has a high degree of formality, control, and documentation, which fits the characteristics of a waterfall approach. References:

[BABOK® Guide], section 2.5: Plan Business Analysis Approach

CCBA Exam Questions & Answers with Explanations, question 418