If you know the Index, Value or Text. also if you don't have an ID for a direct reference.
ThisThis, thisthis and thisthis are all helpful answers.
Example markup
<div class="selDiv"> <select class="opts"> <option selected value="DEFAULT">Default</option> <option value="SEL1">Selection 1</option> <option value="SEL2">Selection 2</option> </select> </div>