The correct option is D Xylem vessels
The xylem tissue is composed of different cells which are involved in the conduction of water and minerals. The xylem vessels are the elongated tube-like dead cells which are the basic component involved in conduction. These are dead cells which are deposited with lignin on the cell walls. They don not have nucleus and protoplasm. Cambium cells, root hair cells and companion cells are living cells and contain the nucleus.