Of the following - sea cucumbers, clams, jellyfishes, sea sausages- are they all living sea-creatures?

I know jellyfish doesn't really have a brain, just a piece of tentacles and things floating around the sea, drifted by the current. What about the rest?|||Ryu, this sea sausage, I am not convinced it is a real organism, your link is hardly convincing - if that photo is of a living organism, it still does not confirm it is a 'sea sausage'. A cursory investigation throws up even more uncertainty. It is described as algae and some kind of tubular seaweed among 'other' descriptions ! No matter, if it is a photosynthetic organism then it is living and yes, it lives in the sea according to some sources. The others are of course living marine organisms. The definition of a living organism does not include having a brain. Plants don't have brains but they are certainly living !|||Sea sausages is the only one on your list I think you just made up. The others I've seen on documentaries and/or magazines if not in real life. (I seen a couple in real life too).|||thay all are living creatures...but sea sausage is not a living creature