The correct option is D Companion cells are part of the epidermal tissue system
Bulliform cells are found in the upper epidermis of monocot leaves and help in the folding of the leaves.
Subsidary cells are parenchymatous cells found around the guard cells of a stomatal apparatus.
Lenticels are openings found in the woody plants in place of the stomata and are formed during the secondary growth of the plant.
Companion cells are one of the cell components of the phloem tissue, the others being sieve tubes, phloem fibers and phloem parenchyma.