Which of the following is not a service desk type recognized in the service operation volume of ITIL?

Local service desk is a recognized ITIL type where the desk is situated close to or within the user community it serves, making it one of the three valid types.

Centralized service desk is a recognized ITIL type where a single desk serves an entire organization from one physical location, reducing costs and improving consistency.

ITIL Service Operation recognizes only Local, Centralized, and Virtual as the three service desk structure types. Outsourcing describes a procurement or delivery strategy for IT services broadly, not a structural classification of a service desk. Because it does not describe how a desk is organized or located, it is not listed among the ITIL-defined types.

Virtual service desk is a recognized ITIL type where geographically dispersed staff use technology to present themselves as a single, unified service desk.