Under which circumstance should you omit saluting a uniformed Commissioned Officer?

The correct choice is based on established military and police protocol regarding saluting. When a uniformed Commissioned Officer is in a vehicle or on public conveyances, it is customary to omit the salute. This practice stems from the understanding that saluting is a formal gesture and should maintain a certain decorum; attempting to salute from within a moving vehicle or while aboard public transportation could disrupt the flow of these situations and may not be practical or safe.

Saluting is generally reserved for situations where both parties are standing and at attention, allowing for a mutual display of respect. During interactions within vehicles or crowded public transport settings, instead of a salute, officers may choose to acknowledge one another in less formal ways that are more conducive to the environment.

In contrast, saluting outdoors, during public engagements, or when in civilian clothing follows different protocols where a salute could be appropriate under the right circumstances. Thus, the context of the situation directly influences the appropriateness of saluting, and the need to omit it specifically in the case of vehicles or public conveyances is well established in official guidelines.