Which real estate document must clearly state the commission arrangement?

The correct response is the listing agreement. This document serves as a contract between the property owner and the real estate agent, specifying the terms under which the agent will represent the owner in the sale of the property. A critical component of the listing agreement is the section detailing the commission arrangement, which defines how much the agent will earn upon the successful sale of the property. By clearly outlining the commission structure, the listing agreement ensures transparency for both the seller and the agent regarding compensation and helps prevent any potential disputes regarding payment after the property is sold.

While other documents mentioned may imply commission arrangements or address fees in some capacity, they do not have the specific requirement to state the commission structure as explicitly and directly as the listing agreement does.