Which soil cannot be rolled into balls or clumps

Your answer would be Sand.

If you go to the beach, and try making balls in your hand it's nearly impossible. If you pick up sand it will just fall through the crevice's in your hand, or a simple movement of your hand can make the sand fall. Sand simply can't be formed into a ball.

If you where to try making a ball of sand the outcome wouldn't be great. Even if you made the sand damp you still can't really make a ball of sand.

organisms that lack symmetry are called asymmetrical and belong to phylum porifera/sponges.

organisms with specialized stinging cells belong to phylum cnidaria. stinging cells are called cnidoblast cells.

cnidarians show two morphological forms : polyp (sessile) and medusa (mobile)

filter feeding is observed in porifera members.  

alternation of generation is observed in coelenterata or cnidaria. there is alternation of asexual polyp form and sexual medusoid form. it is also referred as metagenesis.