Multiple Choice question types are fine because you have more control over the formatting of the Answer Captions.
But Sequence questions are a pain because all of the answers are basically stuck together as a group.
The only workaround that I have found is to insert a blank space just before the answer and format this space to be a larger font size. But you still tend to have some formatting issues with the leading letter in the answer caption.
This is one of the (many) areas that Adobe needs to pick up the text formatting abilities of Captivate.