47. 以下Visual Basic程式執行後，各變數之值為： (A) a = 2, b = 3, x = 2, y = 3　 (B) a = 1, b = 3, x = 2, y = 3 (C)a = 1, b = 2, x = 1, y = 3　 (D)a = 2, b = 2, x = 3, y = 3。 Private Sub Form1_Activated(…)… Dim a, b As Integer a = 1 : b = 2 Call S1(a, b) End Sub Sub S1(ByVal x, ByRef y) x = x * 2 : y = y + 1 End Sub