choose the item of a select

[MassModz]

I need to select a specific item of a combobox in my page when i click in a button.I am using php and javascript code in my page. Actually i am calling a javascript function at the "onclick" of the button. But i still dont get the right command to do this.example:\[code\]<select id="TEST"><option> a</option><option> b</option><option> c</option></select>\[/code\]i want to show the item b when i click in the button.