单项选择题

有如下程序: Private Sub Command1_Click() Dim a As Single Dim b As Single   a=5:b=4   Call Sub1(a,b) End Sub Sub Sub1(x As Single,y As Single)   t=X   X=t\Y   Y=t Mod y End Sub 在调用运行上述程序后,a和b的值分别为

A.0 0
B.1 1
C.2 2
D.1 2