In which section of a requirements document would technical requirements be recorded?

The Requirements Catalogue (or the Requirements Specification section) is the comprehensive, organised list of all types of requirements. Technical Requirements are the non-functional constraints placed on the solution ' s design or build (e.g., specific hardware, operating system compatibility, integration protocols). While these inform other models, they are typically documented and tracked with other requirements (Functional and Non-functional) in the master Requirements Catalogue, often within the Non-functional or System Requirements section of the catalogue structure. Options A, B, and C are supporting documents or models, not the primary repository for a list of technical requirements.

(Reference: BCS Requirements Engineering – Requirements Catalogue Structure)