以下是某个窗体的模块代码,请分析单击窗体后程序运行至"*"号位置时变量X、Y和Z的值分别是 【15】 。 DIM X AS INTEGER DIM Y AS INTEGER PRIVATE SUB FORM_CLICK() DIM X AS INTEGER X=1 Y=1 CALL AA(Y+1) Z=BB(X) ’* * * * * * * MSGBOX "X="&X&"/Y="&Y&"/Z="&Z END SUB PRIVATE SUB AA(BYVAL Z AS INTEGER) Y=Z+X Z=X+Y END SUB PRIVATE FUNCTION BB(BYREF Y AS INTEGER Y=Y+1 BB=X+Y END FUNCTION