l times in order to operate correctly, your list should appear with one of the items initially selected (or with the &quot;apply&quot; trigger disabled).</P>


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Exclusive-None Lists</H3>
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Exclusive-None lists are designed for cases in which either one item must be selected or no items should be selected. For example, a word processor may have a &quot;Justifications&quot; menu with several options such as left-justified, right-justified, or center-justified. Selecting any of these opt