Observe the given diagram representing global biodiversity and answer the question.
Among invertebrates, the order of species richness from low to high is:
(A) Insect
(B) Other animal group
(C) Molluscs
(D) Crustaceans
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → (D), (C), (B), (A)
In the figure the invertebrate sectors rise from crustaceans to molluscs to other animal groups to insects, which are the largest.
Option (1) (C), (B), (A), (D) — Incorrect. Insects have the most species, so they cannot be third.
Option (2) (B), (C), (D), (A) — Incorrect. Other animal groups have more species than molluscs and crustaceans.
Option (3) (D), (C), (B), (A) — Correct. Among invertebrates, species richness rises from crustaceans (D) to molluscs (C), then other animal groups (B), with insects (A) far the richest. So the order from low to high is (D), (C), (B), (A).
Option (4) (C), (A), (B), (D) — Incorrect. Insects are the largest group, so they come last.