CNS is mostly made of

Options

A. motor neurons ans sensory neurons
B. sensory neurons and association neurons
C. association neurons
D. motor neurons and association neurons

Explanation

### Step-by-Step Solution:

1. **Understanding the CNS**: The Central Nervous System (CNS) consists of the brain and spinal cord. It is responsible for processing and integrating information received from the body and coordinating responses.

2. **Components of the CNS**: The CNS is primarily made up of three types of neurons:
- **Sensory Neurons**: These neurons carry signals from sensory receptors to the CNS.
- **Motor Neurons**: These neurons transmit signals from the CNS to muscles and glands to elicit a response.
- **Association Neurons (Interneurons)**: These neurons connect sensory and motor neurons within the CNS and are responsible for processing information.

3. **Identifying the Majority Component**: While sensory and motor neurons are present, the CNS is predominantly composed of association neurons. These neurons play a critical role in processing information and facilitating communication between sensory inputs and motor outputs.

4. **Conclusion**: Based on the understanding of the composition of the CNS, the correct answer to the question "CNS is mostly made of" is **association neurons**.

### Final Answer:
CNS is mostly made of **association neurons**.

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