Correct Answer: a, c, b, d

Solution : Given:
(a) Amoeba (b) Oyster (c) Worm (d) Cow

The following information provides the lengths of different living organisms –
(a) Amoeba = 2.3 micrometres - Amoeba are microscopic, single-celled organisms that typically range in size from 0.02 to 0.03 inches.
(b) Oyster = 2.5 to 3.5 inches - Oysters are bivalve molluscs that can grow up to 3.5 inches in length, with the average size being around 2.5 inches.
(c) Worm = 1 mm to 10 mm - Worms are elongated invertebrates that can vary greatly in size, ranging from less than 1 millimetre to over 10 millimetres.
(d) Cow = 450 to 1800 kg - Cows are large domesticated mammals that can weigh anywhere from 450 to 1800 kilograms, depending on their breed and gender.

So, the sequence is Amoeba, Worm, Oyster, Cow or a, c, b, d. Hence, the first option is correct.