You develop an ASP.NET Web page that includes multiple WebPartZone controls， an EditorZone. Users report that they cannot customize the layout of the page by moving WebParts from one.You need to ensure that users can successfully move Web Parts from one zone to another. What should you do？（）

A.Configure the Web site to enable session state.
B.Configure the Web site to require authentication and to use personalization.
C.Add a ProxyWebPartManager control to the page.
D.Add a AppearanceEditorPart control to the page.