Match List - I with List - II.

	List-I		List-II
(a)	Metamerism	(i)	Coelenterata
(b)	Canal System	(ii)	Ctenophora
(c)	Comb plates	(iii)	Annelida
(d)	Cnidoblasts	(iv)	Porifera

Choose the correct answer from the options given below.

The correct option is a-(iii), b-(iv), c-(ii), d-(i).

Let us analyze the matching pairs between the features in List-I and the corresponding animal phyla in List-II step-by-step:

(a) Metamerism matches with (iii) Annelida:
Metamerism is the phenomenon of having a linear series of body segments fundamentally similar in structure. Annelids (such as earthworms) are well-known for showing true metameric segmentation, where the body is externally and internally divided into segments (metameres).

(b) Canal System matches with (iv) Porifera:
Members of the phylum Porifera (sponges) possess a characteristic water canal system (or water transport system). Water enters through minute pores (ostia) in the body wall into a central cavity (spongocoel), from where it goes out through the osculum. This pathway of water transport is helpful in food gathering, respiratory exchange, and removal of waste.

(c) Comb plates matches with (ii) Ctenophora:
Ctenophores (commonly known as comb jellies or sea walnuts) are characterized by the presence of eight external rows of ciliated comb plates, which help in locomotion.

(d) Cnidoblasts matches with (i) Coelenterata:
Coelenterates (also known as Cnidarians) possess specialized stinging cells called cnidoblasts or cnidocytes on their tentacles and body, which are used for anchorage, defense, and for the capture of prey.

Combining these matches, we get:
a → (iii)
b → (iv)
c → (ii)
d → (i)