During an auditorium opening, what should the class leader announce first?

In the context of an auditorium opening during Officer Training School, the correct approach for the class leader is to create an environment of readiness and respect for the occasion. Announcing “STAND BY” serves as an essential precursor to gaining the attention of the assembly.

This command helps establish a moment of pause before proceeding with further announcements or commands. By setting the tone with “STAND BY,” the leader effectively communicates the need for focus and preparation among those present, which is critical in a formal setting. It acts as a signal to attendees that something important is about to follow, thereby enhancing the overall organization of the event.

The other options pertain to directives that may be too advanced or lack the necessary context for announcing an opening, making "STAND BY" the appropriate choice for commencing the proceedings in a measured and respectful manner.