Question

Organisms found in marine habitats, with skeletal spicules made of calcium carbonate, spongin or silica, multicellular diploblastic body riddled with Ostia, chambers, and canals, belong to
(A)Coelenterata
(B)Porifera
(C)Ctenophora
(D)Annelida

Answer 1

Hint A large portion of them are marine. The body divider is diploblastic, which comprises an external layer, called a pinacoderm, and an inward layer, called a choanoderm.

Complete answer:
Porifera are multicellular creatures, which are inactive in nature. The channel framework essentially contains incurrent and excurrent waterways, which are fixed with pinacocytes, and outspread trenches, which are fixed with choanocytes (flogged cells). The body dividers contain various pores, called Ostia through which water enters the body through a trench framework into the focal body depression called the spongocoel. Its exoskeleton is composed of either spongin filaments of calcareous/siliceous spicules or a mix of both.

Additional information:
There are at any rate 5,000 named types of wipes, likely with thousands all the more yet to be ordered. The morphology of the most straightforward wipes takes the state of an unpredictable chamber with an enormous focal pit, the spongocoel, possessing within the chamber ((Figure)). Water goes into the spongocoel through various pores, or Ostia, that make openings in the body divider. Water entering the spongocoel is ousted by means of an enormous regular opening called the osculum. Notwithstanding, we should take note that wipes show a scope of variety in body structures, remembering varieties for the size and state of the spongocoel, just as the number and course of action of taking care of chambers inside the body divider.

So, the correct answer is ‘Porifera’.

Note: In certain wipes, various taking care of chambers open off of a focal spongocoel, and in others, a few taking care of chambers associated with each other may lie between the section pores and the spongocoel. While wipes don't display genuine tissue-layer association, they do have various utilitarian "tissues" made out of various cell types particularly for unmistakable capacities. For instance, epithelial-like cells called pinacocytes structure the peripheral body, called a pinacoderm, that serves a defensive capacity comparable to that of our epidermis.