The correct answer is B . Selecting the project approach during starting up a project is intended to establish an appropriate basis for how the project will be delivered before the organization commits significant resources to initiation. The delivery method and use of external suppliers can materially influence management controls, commercial arrangements, quality, sustainability, communication, risk, and other management approaches subsequently developed during initiation.

The team has identified an uncertainty arising directly from its proposed approach: a traditional delivery model combined with external suppliers may make sustainability requirements more difficult to achieve. Recording this early in the project log is appropriate because risks, issues, lessons, and other relevant information identified during starting up should not be ignored simply because detailed management approaches have not yet been completed.

Option A is too narrow. Clarifying contractual obligations may be relevant, but it is not the primary rationale demonstrated here. Option C incorrectly suggests that a manageable risk should be deferred; early identification allows it to influence initiation planning and development of the PID. Option D creates a false choice. Sustainability expectations may indeed inform quality requirements, but an uncertainty concerning whether the delivery approach will enable those requirements to be achieved is still legitimately a risk.

PRINCE2 7 reference topics: Starting up a project; select the project approach; project log; early risk identification; sustainability; project initiation documentation.

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