Sub-arachnoid space is present between

Options

A. Cranium and duramater
B. Duramater and arachnoid
C. Arachnoid and pia mater
D. Two lateral ventricles

Answer

To solve the question regarding the location of the sub-arachnoid space, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Components**:
- The brain is covered by three protective membranes known as the meninges: the dura mater (outermost), the arachnoid mater (middle), and the pia mater (innermost).

2. **Identify the Sub-arachnoid Space**:
- The sub-arachnoid space is the area located between the arachnoid mater and the pia mater.

3. **Review the Options**:
- a) Cranium and dura mater
- b) Dura mater and arachnoid
- c) Arachnoid and pia mater
- d) Two lateral ventricles

4. **Analyze Each Option**:
- Option a) refers to the space between the cranium and the dura mater, which is not the sub-arachnoid space.
- Option b) refers to the space between the dura mater and the arachnoid, which is also not the sub-arachnoid space.
- Option c) correctly identifies the space between the arachnoid and pia mater as the sub-arachnoid space.
- Option d) refers to the lateral ventricles, which are fluid-filled spaces in the brain, not related to the sub-arachnoid space.

5. **Conclude the Answer**:
- Based on the analysis, the correct answer is option **c) arachnoid and pia mater**.

### Final Answer:
The sub-arachnoid space is present between the **arachnoid and pia mater**.

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