The epidermis of the xerophytes is covered with a waxy layer called:

Explanation

Cellulose is a tough, fibrous, and water-insoluble polysaccharide that plays an integral role in keeping the structure of plant cell walls stable. Therefore, A is incorrect. The cuticle is a barrier coating the outer surface of epidermal cells of organs of the aerial parts of the plants. It protects against water loss, various abiotic and biotic stress. Therefore, B is correct. Chitin is a fibrous substance consisting of polysaccharides and it is the major constituent in the exoskeleton of arthropods and the cell walls of fungi. Therefore, C is incorrect. Lignin is an important organic polymer that is abundant in the cell walls of some specific cells. It has many biological functions such as water transport, mechanical support, and resistance to various stresses. Therefore, D is incorrect.