Before members of a large assembly can debate or propose motions, what must they do?

Before members of a large assembly can debate or propose motions, they must rise and address the chairman. This procedure is a fundamental aspect of Robert's Rules of Order, which governs parliamentary procedure. By addressing the chairman, a member indicates their desire to speak and ensures that the meeting flows in an orderly manner.

When a member rises to address the chairman, it signals to the presiding officer that they wish to participate in the discussion. The chairman then recognizes the individual, granting them permission to speak. This is crucial in large assemblies where multiple members may wish to contribute, as it helps prevent chaos and ensures that only one person speaks at a time, allowing for clearer and more focused debate.

The other choices do not follow the essential protocols for formal discussion in a parliamentary setting. Voting on the agenda does not precede the ability to debate; submitting a formal motion is a subsequent step after addressing the chairman, and expressing opinions quietly does not contribute to the structured debate intended in a formal assembly. Therefore, the requirement to rise and address the chairman is the key procedural step necessary for members to engage effectively in discussions and put forward motions.