Assuming you've got a custom form with 3 option buttons
and would like a cell (I'm using cell "A1") in "EnqHead"
worksheet to reflect the value selected, you could do the
following:
in the VB-editor double click on the any of the 3 option
buttons and place the following code:

Private Sub optPurch_Click()
Worksheets("EnqHead").Range("A1").Value = "Purchase"
End Sub

Private Sub optReturn_Click()
Worksheets("EnqHead").Range("A1").Value = "Return"
End Sub

Private Sub optSales_Click()
Worksheets("EnqHead").Range("A1").Value = "Sales"
End Sub



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