Q.Which of the following pairs is wrong?

Checking each pairing against the standard classification of nitrogenous excretion:

• Uricotelic – Birds is correct, since birds excrete uric acid to conserve water.
• Ureotelic – Insects is wrong: terrestrial insects are typically uricotelic, excreting largely solid uric acid to minimise water loss, not urea. …

Nitrogenous waste classification follows a consistent logic tied to water availability in an animal's habitat.

• Birds are uricotelic, excreting uric acid as a water-conserving adaptation suited to flight and egg-laying, so the first pair is correctly matched.
• Terrestrial insects, much like birds and reptiles, need to conserve water and typically excrete uric acid through structures such as Malpighian tubules — making them uricotelic rather than ureotelic, so pairing "Ureotelic – Insects" is incorrect. …

Method: Finding the Wrong Pair Among Excretory-Type/Animal Pairings

A close cousin of the statement-checking method used for classification questions, applied specifically when the question presents single-line pairs (Category — Animal) rather than full statements, and asks which pair is wrong.

Steps

Step 1: Treat each pair as a mini true/false claim

Read every "Category — Animal" line as its own standalone claim to be verified, exactly as if it said "this animal belongs to this excretory category." Do not let the visual "list" format make you skim faster than you would a full sentence.

Step 2: Check each animal against the category that its lifestyle demands …