Pre seclecting in a dropdown list

Pre seclecting in a dropdown list

I know this is easy I just can not remember how to do it.

I am getting some info from a DB and putting it in a drop down I would like to know how I can mark one as selected

like
day=tuesday
.
.
<option name="something" if(day == "monday") selected> monday</option>
<option name="something" if(day == "tuesday") selected> tuesday</option>
.
.
.
.

Can someone please help.