I have the following HTML
Just updating in case it helps someone. I had a similar requirement but in my case the dropdown was stored as a JavaScript variable. Also I liked how Denis Matafonov suggested to make the option in question selected. So here's the final block of code:
var target_dd = $('select[name=name]');
$(target_dd).val($(target_dd).find('option:eq(2)').html());