Dominic Morris, CFA, works for a small regional securities firm. According to the Standards of Professional Conduct relating to additional compensation arrangements, which of the following is most accurate（）
A. Morris must not accept compensation for work that competes with his firm's interests.
B. Morris must not accept compensation for work that competes with his firm's interests without written consent from his firm.
C. Morris must not accept compensation for work that competes with his firm's interests without written consent from all parties involved.