Klik tombol radio menggunakan jQuery
$('input:radio[name=sex]:nth(0)').attr('checked',true);
or
$('input:radio[name=sex]')[0].checked = true;
Expensive Eel
$('input:radio[name=sex]:nth(0)').attr('checked',true);
or
$('input:radio[name=sex]')[0].checked = true;