Delete Function on FMEA Worksheet

I am using PTC Windchill Quality Soutions 10.2.  On the FMEA Worksheet tab, I have inserted a number of functions, functional failures, etc.  When I right click on one of these items, the Delete Record arrow is there, but all of the options (Function, Functional Failure, etc) are all greyed out.  It will let me delete all functions, but obviously I don't want to do that.  How do I delete a function on the FMEA Worksheet?