Reptile that is well known for its intense colour change is

Answer: (b) Chameleon

Chameleons change colour dramatically using special skin cells.

The idea

A chameleon’s skin has layers of special cells holding pigments and tiny crystals. By stretching or relaxing the skin it changes how light is reflected, and the colour shifts within minutes. It does this mainly to signal to other chameleons and to control body heat, not only to hide.

Calm: green or brown, matching leaves → Excited or threatened: bright or dark → Cold: darker, to absorb heat

Why the others are wrong

(a) Some lizards change colour, but only slightly.

(c) The glass snake is a legless lizard, not a colour-changer.

The trap

A chameleon IS a lizard, so (a) is not absurd. The question asks for the one known for intense change.

Also know

Other chameleon features: eyes that move separately, a tongue longer than its body that shoots out to catch insects, feet that grip like tongs and a tail that can hold a branch. The Indian chameleon lives in the forests and scrub of peninsular India.