界面如图,代码如下,请问,在两个【】中应该填什么Option ExplicitPrivate Sub Command1_Click()Dim a As Single, b As Single, t As Single, s As Stringa = Val(Text1.Text)b = Val(Text2.Text)Select Case【?】Case Option1.Values = "+"t = a + bCase Option2.Values = "-"t = a - bCase Option3.Values = "*"t = a * bCase Option4.Values = "/"If b <> 0 Thent = a / bElseMsgBox "除数为0"Text2.Text = ""Text2.SetFocusEnd IfEnd SelectIf 【?】 Then Text3.Text = a & s & b & "=" & tEnd SubPrivate Sub Form_Load()Option1.Value = TrueEnd Sub