JavaScript: IIF like statement

Coming from VB, JavaScript isn't very easy to get the hang of. Please don't be negative, I've tried and searched loads but with no luck. BTW, I'm creating a dropdown control initialized from a Select option list in JS.

Dummy code:

var col = 'tardis'; 
var x = '<option value="' + col + '">Very roomy</option>');

I would like to add selected after the value of col ONLY if col is equal to 'screwdriver'.

I've tried using the IF statement with the ? and the : but can't seem to get my head around it. Having '' as the false value does not work. No items are selected and the list is blank. Remove the IF statement and all works.

Any ideas and again, sorry for the newb-ness.