What describes a cloud provider who manages a user's system but is not under user control?

A cloud provider who manages a user's system but is not under user control is accurately described by the term "third-party admin." This refers to an external entity that handles administration and management of cloud services or systems for a user or organization without the user having direct oversight or control over the administration processes.

In the context of cloud computing, third-party administrators typically provide essential services, such as maintenance, monitoring, and updates, often through a managed service model. This arrangement allows users to leverage the expertise and resources of the provider without the burden of managing the underlying infrastructure directly. This is especially important in scenarios where the user may lack the technical resources or expertise to manage complex cloud environments effectively.

The other options do not capture this relationship accurately. A direct administrator implies a user who has control over their cloud environment, whereas internal IT security typically refers to teams within an organization managing their own systems. A full-service provider could refer to a broad range of services but does not specifically emphasize the lack of user control in management—rather, it suggests comprehensive service offerings that could include user management.