Which requirement is explicit in the Circular No. 230 rule on conflicts of interests?

1. The practitioner should retain copies of written consents for at least 36 months from the date representation of the client concluded.

2. The practitioner may not represent an attest client if the practitioner is personally conflicted under any circumstances.

3. The practitioner should send copies of the written consents to the IRSs Office of Professional Responsibility (OPR).

4. The practitioner may not represent a client if such representation adversely affects another of the practitioners clients.