Over the weekend Qualtrics made a change that impacted the ability to edit choices that contain HTML. When you click on the choice containing html nothing happens -- you can't change the text or select from the choice context menu. I reported the problem yesterday and it was escalated.
With the help of Qualtrics Support, I've identified a work around. If you want to edit a choice, click exactly on the left or right edge of the choice box. That will put you in the normal edit mode.
Hopefully, it will be fixed soon.