The current quiz API seems to be missing functionality to insert HTML answers, as one can only set an answer_text and not an answer_html. This is despite the fact that the actual answers support an html element, as can be seen below:
I think that it should always be possible to set values via the API as opposed to having to use the GUI. While it might take only a few minutes to do this for a single question, when there are large numbers of questions - this is when it should be possible to apply power tools.
[I am aware that there will be a new quiz engine, but as I do not have it - I have to work with what I have.]