Final answer:
Sole proprietors must conduct business under a Doing Business As (DBA) name.
Step-by-step explanation:
A sole proprietor must conduct business under a Doing Business As (DBA) name. This is also known as an assumed name or a trade name. A DBA is a fictitious name that is used when a person wants to conduct business under a name that is different from their legal name. It allows sole proprietors to create a separate brand identity without forming a separate legal entity.