According to the PMBOK® Guide and the Agile Practice Guide, selecting the correct delivery approach depends on the degree of uncertainty and the clarity of requirements.

Predictive (Waterfall) Approach: This lifecycle is most suitable when the project requirements are well-defined, stable, and unlikely to change significantly. In the case of a new tax law, the requirements are typically prescriptive—the government provides specific rules, percentages, and deadlines that the accounting system must adhere to.

Fixed Deadlines and Scope: The prompt mentions a specific one-year timeline. A predictive approach allows for a structured, sequential flow (Analysis → Design → Build → Test → Deploy) which is ideal for compliance-driven projects where the " definition of done " is non-negotiable and dictated by external regulations.

Low Uncertainty: Because the law is already published, the " what " of the project is known. The project team can plan the entire scope in detail at the beginning of the project, establishing a clear Schedule Baseline to ensure the one-year deadline is met.

Analysis of other options:

Option A: While the risk of fines is real, the risk itself does not dictate the delivery approach; the stability of requirements does. High risk can exist in both adaptive and predictive projects.

Option C: This is incorrect because governments rarely provide " constant feedback " during a system implementation; they provide the law, and the company must comply. Adaptive approaches rely on frequent stakeholder interaction to define the path forward, which is unnecessary when the rules are already set.

Option D: " Never been implemented before " often suggests a need for innovation, but in the context of legal compliance, it doesn ' t automatically require an adaptive approach. If the instructions (the law) are clear, a predictive approach is more efficient for ensuring every legal requirement is checked off.

Per PMI standards, a Predictive approach is the best choice for regulatory and compliance projects where the scope is fixed by law and the primary goal is meeting a specific, predetermined outcome by a hard deadline.