The correct option is B Mollusca
The molluscs have a calcareous shell covering the body. However, a soft and spongy layer of skin is present over the visceral hump of molluscs, forming the mantle. Echinoderms do not have a soft body. They have calcareous endoskeleton making it spiny bodies. Poriferans have pores all over the body. Therefore, they are also not soft bodied. Moreover, sponges also bear spicules or spongin fibres.