Why not try a tool tip for that list member? When the respondent hovers their mouse over that list member label, the tool tip will appear in a window. Give it a try.
I would suggest you insert an instruction to assist the respondent also.
The format is as follows: ToolTip("LinkText", "HelpText", Width, Height)
[%ToolTip("New York","Very big city in the USA.",320,15)%]