CNS includes

Options

A. Brain and spinal cord
B. Afferent and efferent fibres
C. Sympathetic and parasympathetic system
D. Both (a) and (c )

Answer

### Step-by-Step Solution:

1. **Understanding CNS**: The question asks about the components of the Central Nervous System (CNS). CNS is a crucial part of the nervous system that controls various functions of the body and mind.

2. **Identifying the Components**: The CNS primarily consists of two main structures: the brain and the spinal cord. The brain is responsible for processing information and controlling thoughts, while the spinal cord serves as a pathway for signals between the brain and the rest of the body.

3. **Evaluating Options**:
- **Option 1: Brain and Spinal Cord**: This is correct as both structures are integral parts of the CNS.
- **Option 2: Afferent and Efferent Fibers**: This is incorrect. While these fibers are involved in the nervous system, they are not part of the CNS itself; they are part of the peripheral nervous system that connects to the CNS.
- **Option 3: Sympathetic and Parasympathetic Systems**: This option is also incorrect. These systems are components of the autonomic nervous system, which regulates involuntary bodily functions, but they do not constitute the CNS.
- **Option 4: Other Options**: Since the first option is correct, we can conclude that it is the only valid answer regarding the components of the CNS.

4. **Conclusion**: Therefore, the CNS includes the brain and spinal cord.

### Final Answer:
CNS includes the brain and spinal cord.

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