Grey matter is :

Options

A. located on the outside of the spinal cord
B. restricted to the brain
C. populated by cell bodies of neurons
D. found in the ventricles of the vertebrate brain

Explanation

**Step-by-Step Solution:**

1. **Understanding Grey Matter**: Grey matter is a major component of the central nervous system (CNS). It primarily consists of neuronal cell bodies, unmyelinated axons, dendrites, and glial cells.

2. **Analyzing the Options**:
- **Option A**: "Located on the outside of the spinal cord."
- This is incorrect because grey matter is actually located on the inside of the spinal cord, while white matter is on the outside.

- **Option B**: "Restricted to the brain."
- This is also incorrect. Grey matter is found in both the brain and the spinal cord.

- **Option C**: "Populated by cell bodies of neurons."
- This is correct. Grey matter is indeed populated by the cell bodies of neurons, which is a defining characteristic of grey matter.

- **Option D**: "Found in the ventricles of the vertebrae."
- This is incorrect as well. The ventricles contain cerebrospinal fluid, not grey matter.

3. **Conclusion**: After analyzing all the options, the correct answer is that grey matter is "populated by cell bodies of neurons."

**Final Answer**: Grey matter is populated by cell bodies of neurons.

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