To solve this question, the user needs to have knowledge of the Framework Manager environment in IBM Cognos Analytics. In this environment, different objects are used to organize and manage data and metadata.

The object that acts as a container and provides a unique name for objects in the Framework Manager environment is the Namespace.

A Namespace is a container that groups related objects, such as Query Subjects, Query Items, Filters, and Calculations. It provides a unique name for each object within its scope, ensuring that there are no naming conflicts between objects.

Option A, Model, is incorrect because it is a higher-level object that contains multiple namespaces and is used to organize and manage data sources and metadata in Framework Manager.

Option B, Query Item, is incorrect because it is a specific data item that is used in a query or report. It does not act as a container or provide a unique name for objects.

Option D, Query Subject, is incorrect because it is an object that defines a set of related data items that can be used in a query or report. It does not act as a container or provide a unique name for objects.

Therefore, the correct answer is:

The Answer is: C. Namespace