下列程序的执行结果为( )
Private Sub Command1_Click()
Dim x As Integer,y As Integer
x=12:y=20
Call Value(X,y)
Print x;y
End Sub
Private Sub Value(ByVal m As Integer,ByVal n As Integer)
m=m * 2:n=n-5
Print m; n
End Sub

A．20 12
20 15
B．12 20
12 25
C．24 15
12 20
D．24 12
12 15

图书馆图书实行开架借阅，未办理借阅手续者不得自行将图书带出书库。