Match the following and choose the correct answer.

	List-I		List-II
(a)	Physalia	(i)	Pearl oyster
(b)	Limulus	(ii)	Portuguese Man of War
(c)	Ancylostoma	(iii)	Living fossil
(d)	Pinctada	(iv)	Hookworm

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

Let us match the organisms listed in List-I with their common names or characteristics in List-II step-by-step:

1. (a) Physalia: Physalia (commonly known as Physalia physalis) belongs to the phylum Coelenterata (Cnidaria). It is famously known as the Portuguese Man of War because of its resemblance to an 18th-century Portuguese warship at full sail. Therefore, a matches with (ii).

2. (b) Limulus: Limulus (commonly known as the king crab or horseshoe crab) belongs to the phylum Arthropoda. It is referred to as a Living fossil because it has remained virtually unchanged for millions of years and has no close living relatives. Therefore, b matches with (iii).

3. (c) Ancylostoma: Ancylostoma belongs to the phylum Aschelminthes (Nematoda). It is a parasitic nematode commonly known as the Hookworm, which infects the small intestine of humans and other mammals. Therefore, c matches with (iv).

4. (d) Pinctada: Pinctada belongs to the phylum Mollusca. It is a genus of saltwater oysters, commonly known as the Pearl oyster, which is highly valued for producing marine pearls. Therefore, d matches with (i).

Combining all the correct matches, we get:
a - (ii), b - (iii), c - (iv), d - (i).