.NET Framework Class Library: identify the option that is NOT a valid namespace.

Introduction / Context:
Distinguishing between namespaces and types prevents import and reference errors. This item tests recognition of actual .NET namespaces.

Given Data / Assumptions:

• Only one of the listed entries is not a namespace.
• Process is a type in System.Diagnostics.

Concept / Approach:
Recall common namespaces: System.Security, System.Threading, System.Drawing, and System.Xml exist. Process itself is not a namespace; it is a class used to start and manage processes.

Step-by-Step Solution:

Verification / Alternative check:
Use an IDE object browser or official docs; you will find Process under System.Diagnostics.

Why Other Options Are Wrong:
They are legitimate namespaces.

Common Pitfalls:
Confusing a type name with a namespace path (e.g., thinking System.Process parallels System.Threading).

Final Answer:
System.Process