The correct option is B endodermis
The stele is the central region of the roots and stems. Pericycle, pith, and vascular tissues are the components of stele.
The pericycle is made up of a few layers of thick-walled parenchyma cells that help in the formation of lateral roots and vascular cambium.
Xylem is the water-conducting vascular tissue.
Pith is the central most region in roots and stems and is made up of parenchyma cells.
The endodermis is the innermost layer of the cortex and is not a component of stele.