The outer surface of the epidermis is covered by a waxy coating called .

The correct option is B cuticle
The outer surface of the epidermis has a waxy coat called cuticle covering it. It prevents the loss of water. This is seen only in the stem and is absent in the roots. Dermis is the layer below the epidermis, guard cells are parenchymatous cells which are part of the stomata, a type of epidermis. Trichomes are epidermal appendages.