Concept: Birds build nests to lay their eggs and incubate their younger ones. Different birds build nests at different places, some on ground level, some high up on the tree. Different birds use different techniques and different materials to build their nests. Explanation: The dove makes its nest among the thorns of a cactus plant or a Mehendi hedge. The sparrow and pigeon make their nest anywhere on top of a cupboard, behind a mirror, on a ledge. The barbet or coppersmith bird makes its nest in a hole, in a tree trunk. A crow’s nest is made of all kinds of things, even pieces of wire and wood. The crow builds its nest high up on a tree. The tailorbird uses its sharp beak to make its nest by stitching together two leaves on a bush. It lays its eggs in the fold of the leaf that it has made. The sunbird makes a nest that hangs from the branch of a small tree or a bush. The robin makes its nest with soft twigs, roots, wool, hair and cotton wool at ground level alongside road, lower branches of a tree or sometimes at the top. ​Thus, the correct match is (a) - (iii), (b) - (i), (c) -(iv), (d) - (ii) List-I (Bird) List-II (Nest) (a) Dove (iii) thorn of the cactus plant (b) Crow (i) high up on a tree (c) Sparrow (iv) top of a cupboard (d) Robin (ii) along the roadside