The stele consists of

Options

A. only vascular bundles
B. vascular bundles, pericycle, pith and medullary rays
C. vascular bundles, pericycle and pith
D. vascular bundles and pith

Answer

### Step-by-Step Solution:

1. **Definition of Stele**: The stele is the central part of the root or stem in vascular plants. It is important to understand that the stele contains various types of tissues.

2. **Tissues Derived from Procambium**: The tissues that make up the stele are derived from a tissue called procambium, which is responsible for forming vascular tissues.

3. **Components of the Stele**:
- **Vascular Bundles**: These are the primary components of the stele, which include xylem and phloem tissues responsible for the transport of water, nutrients, and food.
- **Pericycle**: This is a layer of cells that surrounds the vascular bundles and is involved in the formation of lateral roots.
- **Pith**: This is the central part of the stele that consists of parenchyma cells, which may store nutrients and provide support.

4. **Other Structures**:
- The endodermis lies outside the stele and is the innermost layer of the cortex.
- Medullary rays are present between the vascular bundles but are not considered part of the stele itself.

5. **Correct Answer**: Based on the components described, the correct option is that the stele consists of vascular bundles, pericycle, and pith.