A、SELECT 职员号 FROM 订单 GROUP BY 职员号 HAYING COUNT(*)>3 AND AVG_金额>200
B、SELECT 职员号 FROM 订单 GROUP BY 职员号 HAVING COUNT(*)>3 AND AVG(金额)>200
C、SELECT 职员号 FROM 订单 GROUP BY 职员号 HAVING COUNT(*)>3 AND WHERE AVG(金额)>200
D、SELECT 职员号 FROM 订单 GROUP BY 职员号 WHERE COUNT(*)>3 AND AVG_金额>200
B