Final answer:
The contract for a listing agreement usually requires the term of the listing, the broker's authorization to post signs, and the seller's obligation to inform the broker of the condition of the property. The correct options are (a),(b) and (c).
Step-by-step explanation:
In a listing agreement, certain elements are typically required to be included. One such element is the term of the listing, which indicates the duration of the agreement between the seller and the broker. Another requirement is the broker's authorization to post signs on the property, allowing for marketing and advertising.
Additionally, it is common for the listing agreement to have a clause that requires the seller to inform the broker of the condition of the property. This is important as it ensures transparency and helps the broker accurately represent the property to potential buyers.