Final answer:
Circular 230 includes rules on who is authorized to practice before the IRS, standards for 'covered opinions,' and best practices for practitioners. Compliance with state ethical requirements is not included.
Step-by-step explanation:
Circular 230 is a set of rules published by the Internal Revenue Service (IRS) that govern the practice of tax professionals who represent clients before the IRS.
It includes rules on who is authorized to practice before the IRS, standards for 'covered opinions,' and best practices for practitioners. However, compliance with state ethical requirements is not specifically included in Circular 230.