Code:
 Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        ComboBox1.Items.Add("1")
        ComboBox1.Items.Add("2")
        ComboBox1.Items.Add("3")
        ComboBox1.Items.Add("4")
        ComboBox1.SelectedIndex = 0


    End Sub