Before disseminating changes in his firm’s buy/sell list. Johnson, a CFA candidate, calls his best clients to apprise them of the pending change. Based on the AIMR Standards of Professional Conduct, what standard, if any, did Johnson violate（）
A. Standard Ⅲ (B), Fair Dealing.
B. Standard Ⅳ (B), Priority of Transactions.
C. Standard Ⅱ (A), Prohibition Against Use of Material Nonpublic Information.
参考答案：A
解析：
Standard Ⅲ(B) Fair Dealing. Johnson violated the standard on fair dealing because he did not deal fairly and objectively with all clients and prospects when disseminating investment recommendations. Instead, he showed favoritism to his best clients. In disseminating investment recommendations, Johnson should consider making the information available to clients based on their interest and suitability. A change of recommendation from buy to sell or sell to buy is generally material.