You can't. Drop-down elements can't support HTML. Not a limitation of CB, but a limitation to HTML all together; it would not validate or even work without custom code such as ajax or maybe dhtml.

Best I can suggest is to use CSS to achieve what you're wanting. Example as follows.

[code:1]
#cb_dropdown option[value=Value1] {
background-color: red;
}
[/code:1]

The above is for the field cb_dropdown and the first value is Value1. Simply adjust as necessary. Example of complete drop-down as follows.

[code:1]
#cb_dropdown option[value=Value1] {
background-color: red;
}

#cb_dropdown option[value=Value2] {
background-color: blue;
}

#cb_dropdown option[value=Value3] {
background-color: green;
}
[/code:1]

It would be better to use Firebug for Firefox and inspect the drop-down and use the options actual IDs, but changing the background based on value is a more understandable and user friendly approach.

You can of course change it from a color to an actual background image. More on CSS usage can be found here .