Final answer:
A) Mary is entitled to both the seller's and buyer's agent commission for the transaction.
Mary, acting as a seller's agent, would be entitled to both the seller's and buyer's agent commission if the transaction is completed and if such terms are agreed upon in the listing agreement since she is acting in a dual agency capacity.
Step-by-step explanation:
Mary showed Tom her listing as a seller's agent. She also showed him other properties listed with other brokerages. When Tom decided to put an offer on Mary's listing, the issue of commission arises. In typical real estate transactions, the commission is often split between the seller's agent and the buyer's agent. However, in this scenario, Mary is working as the seller's agent and has introduced the buyer to her own listing. This situation can be referred to as a double-ended or dual agency transaction, where one agent represents both the seller and the buyer.
Given the information provided and barring any agency agreements or local laws to the contrary, the answer is: A) Mary is entitled to both the seller's and buyer's agent commission for the transaction. This is because Mary, as the agent, has performed the roles of both the selling agent (representing the seller) and, implicitly, the buying agent (by showing the property to the buyer). Thus, assuming the seller and Mary, as the listing agent, have agreed to such terms where she is allowed to act in a dual capacity, she would be entitled to the full commission outlined in the listing agreement.