VBA code required to delete contents of a range and prevent further input.

Figured it out in the end. Phew!

Private Sub Worksheet_Change(ByVal Target As Range)
On Error GoTo ReEnableEvents
Application.EnableEvents = False
If Target.Address = Range("D8").Address Then
Select Case UCase(Target.Value)
Case ""
Application.Undo
GoTo ReEnableEvents
Case UCase("Option 1")
Range("F10:F48").ClearContents
Case UCase("Option 2")
Range("F10:F48").ClearContents
Case UCase("Option 3")
Range("F10:F48").ClearContents
Case UCase("Option 4")
Range("F10:F48").ClearContents
End Select
End If
ReEnableEvents:
Application.EnableEvents = True

If Intersect(Target, Range("F10:F48")) Is Nothing Then Exit Sub
On Error GoTo ExitPoint
Application.EnableEvents = False
If Range("D8").Value <> "Option 5" Then
Application.Undo
MsgBox "Cell D8 must be Option 5 in order to input to this cell", vbCritical, "Error"
End If
ExitPoint:
Application.EnableEvents = True
End Sub