Which document must be posted conspicuously on the premises where selling occurs?

The requirement to post a salesperson's license conspicuously on the premises where selling occurs serves several important purposes. Primarily, it ensures transparency and accountability in sales practices. By having the license displayed, customers can verify that the individual they are dealing with is authorized and trained to conduct sales, fostering trust in the transaction. This also helps regulatory authorities and potential customers to easily identify licensed professionals and navigate the sales landscape with confidence.

Having the salesperson's license on display can also assist in compliance with state or local regulations that govern sales transactions, particularly in industries that have strict licensing requirements. This openness can lead to enhanced customer satisfaction, as consumers feel safer knowing they are dealing with a recognized and certified salesperson.

In contrast, the other options, such as the dealer's license, the certificate of installation, or the sales agreement, do not fulfill the same role in directly communicating the salesperson's qualifications to the customer on-site during the sales process. Therefore, showing the salesperson's license is the most appropriate document to be posted conspicuously in a selling environment.