According to CFA Standards, which is least likely to require disclosure to clients?

(A) Referral fees
(B) Personal holdings
(C) Pay from tutoring CFA candidates in spare time
(D) All of the above

The answer is: (C) Pay from tutoring CFA candidates in spare time
Outside compensation (like tutoring) must be disclosed to employers, not to clients, since it does not create a conflict with client interests.