Well let me guess, the reason why you have placed Muslims on the top is because you see them engage in more religious activities more often than the others is it?
Well I wont say NO to this, because in my perspective Muslims are more attached to their religion more than the others.But I am emphasising, this is purely a comparative statement.
But what should be really looked into is, the fact whether the inner rules of the religions are obeyed, and a true believer is created.
This includes the moral values, the social and ethnic behaviour and also the understanding of the religion as well.