Quiz score does not add up correctly

I was able to trouble shoot this and what I found was very strange.   I sent the file to technical support, they ran it and the quiz sequence ran and scored perfectly.  I ran the file on a different laptop I have and the quiz continued to score incorrectly. Both laptops are Toshibas.   I decided to copy the scene into a new file and it still did not score the quiz correctly.  So as a last resort, and something I did not think could work was to see if one quiz side was causing the problem.  Now, technical support told me the slides are not likely to be corrupted since it scored correctly on their computer, but I did it anyway.   I edited the quiz results slide to score only slides that were opened, moved the quiz results slide up in the sequence one slide at a time, eliminating the lowest slide in the sequence from being scored.  The results actually got more and more incorrect as I did this until I eliminated the third quiz slide in the sequence. Now, this slide was nothing more than a copy of the previous 2 slides.  The second slide was a copy of the first pick one slide and it worked correctly, but the third slide, the second pasting of the copy, did not.  I am not sure why this is, maybe making a copy of a copy did something to the slide, but if it did something, the entire sequence worked for technical support as is, but didnt work on either of my laptops.   After eliminating that third slide, reimporting it into the sequence, everything scored correctly.   I dont know if this will help anyone else, but maybe it will save some other person a bit of wasted time.