The correct answer is A . The purpose of the business case is to provide the information needed to determine whether the project represents a desirable, viable, and achievable investment. Developing that justification requires the project to evaluate credible alternatives rather than assuming that the initially proposed solution is automatically the optimum investment.

The option without the underground car park is described as credible. It is therefore appropriate for the project manager to include an investment appraisal of that option so that decision-makers can compare its costs, benefits, risks, dis-benefits, and overall value with those of the preferred solution. The main contractor’s objection does not remove the project’s responsibility to examine legitimate business alternatives; supplier preferences must not determine investment justification.

Option B is incorrect because PRINCE2 does not impose a universal requirement for customer and supplier organizations to maintain completely separate business cases. Option C incorrectly treats initial scope as immutable. During development of the business case, alternative configurations can be evaluated when this helps determine the most appropriate investment. Option D similarly assumes that one anticipated benefit—parking income—precludes examination of other options. A benefit is an input to investment appraisal, not a reason to suppress alternatives.

The scenario therefore demonstrates objective option appraisal as part of sound business justification.

PRINCE2 7 reference topics: Business case practice; business options; investment appraisal; justification; desirability, viability and achievability; initiating a project.

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