程序结构问题

Question

type
  TForm1 = class(TForm)
    Button1: TButton;
    Button2: TButton;
    Button3: TButton;
    Button4: TButton;
  private
    { Private declarations }
  public
    { Public declarations }
  end;其中
    Button1: TButton;
    Button2: TButton;
    Button3: TButton;
    Button4: TButton;
是什么权限，是public 还是private 还是publish 还是protected ?????