VB.Net ComboBox.SelectedIndex always reverts to 1 - vb.net

Question

I am writing a Rock-Paper-Scissors game and have to use a ComboBox to get the user's selection. The problem is that no matter what I select, the selected index always reverts to 1, thus the user always selects rock. How can I fix this?
Imports System.Random
Public Class Form1
Dim played As Integer = 0
Dim won As Integer = 0
Dim lost As Integer = 0
Dim draw As Integer = 0
Dim percent As Single = 0.0
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Label3.Visible = False
End Sub
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim a As New Random()
Dim b As Integer = a.Next(1, 4)
Dim selection As Integer
ComboBox1.SelectedIndex = selection
If b = 1 Then
Label3.Text = "Rock"
Label3.Visible = True
Select Case selection
Case selection = 1
MsgBox("Draw.")
draw += 1
Case selection = 2
MsgBox("Paper Covers Rock. You win!")
won += 1
Case selection = 3
MsgBox("Rock Crushes Scissors. You lose.")
lost += 1
End Select
ElseIf b = 2 Then
Label3.Text = "Paper"
Label3.Visible = True
Select Case selection
Case selection = 1
MsgBox("Paper Covers Rock. You lose.")
lost += 1
Case selection = 2
MsgBox("Draw.")
draw += 1
Case selection = 3
MsgBox("Scissors Cuts Paper. You win!")
won += 1
End Select
ElseIf b = 3 Then
Label3.Text = "Scissors"
Label3.Visible = True
Select Case selection
Case selection = 1
MsgBox("Rock Crushes Scissors. You win!")
won += 1
Case selection = 2
MsgBox("Scissors Cuts Paper. You lose.")
lost += 1
Case selection = 3
MsgBox("Draw.")
draw += 1
End Select
End If
played += 1
percent = (won / played) * 100
PlayedText.Text = played.ToString
WonText.Text = won.ToString
LostText.Text = lost.ToString
DrawText.Text = draw.ToString
PercentText.Text = percent.ToString
End Sub
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
Me.Close()
End Sub
End Class

Answer 1

I think you need to change this line to
Dim selection As Integer
selection = ComboBox1.SelectedIndex
and the syntax for the SELECT....CASE is
Select Case selection
Case 1
MsgBox("Draw.")
draw += 1
Case 2
MsgBox("Paper Covers Rock. You win!")
won += 1
Case 3
MsgBox("Rock Crushes Scissors. You lose.")
lost += 1
End Select