InfoPath Dev

Is it possible to be able to select multiple options from a drop down list created in InfoPath? The trick is that the drop down list is set to be altered to which region you choose first. So if you choose region A, then the drop down list options are A, B , C etc., but if you choose Region B.. the drop down options are F, G, H, etc. so I need that rule to stay. Thanks!!!

 Multi select controls are bound to repeating fields - but you can still have a filter on them so that they are cascading.