I need step by step assistance in setting up a dropdown list which allows
each of the items in the list to have a drop down. I have been referred to
data validation, however I aparently am to dumb to understand how it is
supposed to work, following the example does not five me what I need.

My list needs to be dependent on cell C7 and P8. If C7="SF"and P8="1", then
I need a list in cells D16:D26 which has: Base, EXT, INT, Xtra, Other and
then each of those should allow a drop down to allow a selection of 4 - 9
different operations. I also need this to display in D16 or which ever cell I
am in D16:D26

If someone can suggest how to get this far, I think I could add the other 3
possible scenarios

Thanks for any assistance