Which of the following best describes the document that creates an agency relationship between a seller and a broker?

An offer to purchase is a document submitted by a potential buyer to express interest in buying a property. It indicates the buyer's intent and terms but does not create an agency relationship with the seller. Instead, it outlines the buyer's proposal for acquiring the property, making it unrelated to the seller-broker relationship.

A contract to sell is a legal agreement between a seller and a buyer once an offer has been accepted. While it formalizes the sale of the property, it does not establish the agency relationship between the seller and the broker. This document comes into play after the broker has facilitated the sale but does not define their role in the initial marketing and representation.

An option agreement grants a buyer the right to purchase a property at a specified price within a designated timeframe. While it involves a seller and a buyer, it does not pertain to the relationship between a seller and a broker. Option agreements are focused on the buyer's rights rather than the broker's agency role in the property sale process.