If you're using this tip, there are a few things to be aware of.
You don't need to setup the list of options on a worksheet, you can just type the items into the Source box on the Data Validation dialog. ie Enter Yes,No,Don't Know to get these options.
If you are using a list on a worksheet, but don't want to put it on the same worksheet as the validated cells, name the range your using (Insert/Name/Define) then use that name when you enter the Source. ie If you range is named "Choices", enter "=Choices".
The Validation dialog won't allow direct references to other sheets, but using the named range gets around the limitiation.
Hope these help.
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