Which of the following is NOT considered a banner marking?

A banner marking is a classification designation that appears prominently on the cover of a document to clearly convey the sensitivity level of the information contained within. Typical banner markings include designations such as TOP SECRET, CONFIDENTIAL, and SECRET, as they are used to indicate specific levels of classified information and are recognized standards within the classification system.

In this context, the term "Classified Open" does not represent a recognized classification level or banner marking. It does not fit into the established categories of classified information, which are designed to convey specific sensitivity levels to the information. Therefore, this option stands out as it does not conform to the established classification marking conventions that are intended to ensure proper handling and protection of classified materials.