Meninges are :

Options

A. A) spinal tracts that carry impulses up the spinal cord
B. B) grey matter masses within the spinal cord
C. C) bundles of axons outside the central nervous system
D. D) connective tissue coverings around the brain and cord

Explanation

### Step-by-Step Solution:

1. **Understanding Meninges**: Meninges are the protective membranes that cover the brain and spinal cord. They play a crucial role in providing support and protection to the central nervous system (CNS).

2. **Functions of Meninges**: The primary functions of the meninges include:
- Providing a supportive network for the brain and spinal cord.
- Anchoring the CNS in place to prevent excessive movement within the skull.

3. **Layers of Meninges**: There are three distinct layers of meninges:
- **Dura Mater**: The outermost layer, tough and protective.
- **Arachnoid Mater**: The middle layer, which has a web-like appearance.
- **Pia Mater**: The innermost layer, which is delicate and closely adheres to the surface of the brain and spinal cord.

4. **Evaluating the Options**:
- **Option 1**: Spinal tracts that carry impulses up the spinal cord. This is incorrect as spinal tracts are not meninges.
- **Option 2**: Grey matter within the spinal cord. This is also incorrect since grey matter is a component of the spinal cord itself, not a covering.
- **Option 3**: Bundles of axons outside the CNS. This is incorrect as meninges are located within the CNS.
- **Option 4**: Connective tissue coverings around the brain and cord. This is the correct option, as it accurately describes the meninges.

5. **Conclusion**: The correct answer is that meninges are connective tissue coverings around the brain and spinal cord.