Which of the following motions relates to changing the order of business?

The correct choice reflects a category of motions used specifically to modify the order of business in a formal meeting setting. Subsidiary motions allow members to alter the agenda or add items for discussion, thus changing the order in which business is considered. This is particularly important in a structured meeting environment where the flow of discussion can significantly impact decision-making.

In contrast, main motions introduce new business to the assembly or organization and have a primary purpose of initiating discussion on a particular issue, rather than changing the order of proceedings. Incidental motions are typically procedural and address issues that arise in the course of a meeting, therefore they do not primarily focus on the arrangement of the meeting's agenda. Privileged motions, while important, relate to urgent matters that need immediate attention and are also not primarily about altering the order of business.

Understanding these classifications clarifies why subsidiary motions are the correct answer in the context of altering agenda items or the sequence of discussions in a meeting.