A written disclosure of agency representation is mandatory for transactions involving how many residential units?

Disclosures of agency representation are not mandatory for commercial transactions or transactions involving five or more residential units. The correct option is A because it refers to one to four unit residential transactions, which includes single-family homes, duplexes, triplexes, and fourplexes. These are the most common types of residential units and therefore, it is important for the disclosure to be mandatory in these situations to ensure transparency and protect both parties involved in the transaction.