During technical research, which of the following should be validated?

The focus of the question is on the key elements that should be validated during technical research. The correct option lists National Stock Number (NSN), Unit of Issue (U/I), Unit of Purchase (U/P), and Stock Availability Code (SAC) as critical components for validation.

Validating the NSN is essential because it uniquely identifies an item of supply within the supply chain, ensuring the correct item is referred to throughout the requisition and procurement processes. The unit of issue provides clarity on how the item is packaged for distribution, which affects inventory levels and requisition quantities. The unit of purchase is equally important, as it denotes the quantity at which an item is ordered or purchased, which is vital for accurate budgeting and planning. Lastly, the Stock Availability Code indicates the immediate availability of a requisitioned item, which is crucial for effective supply chain management and operational readiness.

Overall, this combination of elements ensures a smooth process in the requisition and supply chain management, which is why they are closely examined and validated during technical research.