A component of xylem is

Options

A. sieve tube
B. medullary ray
C. Sclereids
D. Tracheid

Answer

To solve the question "A component of xylem is," we will analyze the given options one by one to identify which one correctly represents a component of xylem.

### Step-by-Step Solution:

1. **Identify the Options**: The options provided are:
- Sieve tube
- Medullary rays
- Sclerides
- Tracheids

2. **Analyze Sieve Tube**:
- Sieve tubes are part of the phloem, not xylem. They are responsible for the transport of nutrients, particularly sugars, in plants.
- **Conclusion**: Sieve tube is **not** a component of xylem.

3. **Analyze Medullary Rays**:
- Medullary rays, or vascular rays, are involved in the radial transport of water and nutrients but are not considered a primary component of xylem.
- **Conclusion**: Medullary rays are **not** a component of xylem.

4. **Analyze Sclerides**:
- Sclerides are a type of sclerenchyma cell that provides structural support. They are primarily found in the cortex and pith of gymnosperms and are not specific to xylem.
- **Conclusion**: Sclerides are **not** a component of xylem.

5. **Analyze Tracheids**:
- Tracheids are elongated, dead cells that are a fundamental component of xylem. They have thickened cell walls and are involved in the conduction of water.
- **Conclusion**: Tracheids are indeed a component of xylem.

6. **Final Answer**:
- Based on the analysis, the correct answer to the question "A component of xylem is" is **Tracheids**.