According to the PMBOK® Guide, specifically within the Validate Scope process, Inspection is the primary tool and technique used to ensure that deliverables meet the documented requirements and acceptance criteria.

Definition of Inspection: Inspection includes activities such as measuring, examining, and validating to determine whether work and deliverables meet requirements and product acceptance criteria.

The Validate Scope Process: This process is the formal acceptance of the completed project deliverables by the customer or sponsor. It differs from Control Quality because while quality control is about " correctness, " Validate Scope is about " acceptance. "

Alternative Names: Depending on the industry and the nature of the work, inspections may also be called reviews, product reviews, audits, or walkthroughs. In this scenario, the sponsor ' s act of " measuring and examining " is a textbook definition of an inspection to confirm the deliverable is ready for formal sign-off.

Analysis of other options:

Prototyping (Option B): This is a tool used during the Collect Requirements process to obtain early feedback on requirements by providing a working model of the expected product. It occurs at the beginning of development, not at the final verification stage.

Decision making (Option C): While a decision (accept or reject) will be made based on the inspection, the specific activity of examining the deliverable is called inspection. Decision-making techniques (like voting or multicriteria decision analysis) are the methods used to reach a conclusion.

Brainstorming (Option D): This is a data-gathering technique used to generate and collect multiple ideas related to project and product requirements. It is not used for verifying technical deliverables against criteria.

Per PMI standards, Inspection is critical to the Validate Scope process as it provides the objective evidence needed for the sponsor to formally accept the project ' s output, leading toward project closure.