Arbor vitae is composed of
(a) Grey matter
(b) White matter
(c) Neuroglia cells
(d) All of above

Options

A. Grey matter
B. White matter
C. Neuroglia cells
D. All of above

Answer

To solve the question "Arbor vitae is composed of," we will analyze each option provided:

1. **Understanding Arbor Vitae**:
- Arbor vitae, which translates to "tree of life," is a structure located in the cerebellum of the brain. It is characterized by its tree-like appearance.

2. **Analyzing the Options**:
- **(a) Grey matter**: Grey matter primarily consists of neuronal cell bodies and is found in various regions of the brain and spinal cord. However, arbor vitae does not consist of grey matter.
- **(b) White matter**: White matter is composed of myelinated axons and is responsible for the transmission of signals between different parts of the brain. Arbor vitae is primarily made up of white matter.
- **(c) Neuroglia cells**: Neuroglia, or glial cells, support and protect neurons but are not the primary component of arbor vitae.
- **(d) All of the above**: This option suggests that arbor vitae is composed of grey matter, white matter, and neuroglia cells, which is incorrect since it is primarily white matter.

3. **Conclusion**:
- Based on the analysis, the correct answer is **(b) White matter**. Arbor vitae is composed mainly of white matter, which facilitates the conduction of motor and sensory impulses in the cerebellum.

### Final Answer:
(b) White matter