Which of the following is mismatched?

Options

A. Cerebrum-consciousness
B. Thalamus-motor and sensory centres
C. Hypothalamus-internal environment regulator
D. Cerebellum-motor coordination

Explanation

To solve the question of which option is mismatched, we will analyze each of the provided options regarding their functions in the nervous system.

### Step-by-Step Solution:

1. **Cerebrum - Consciousness**:
- The cerebrum is responsible for higher brain functions, including consciousness, thought, emotion, and sensory processing. This statement is correct.

2. **Thalamus - Motor and Sensory Centers**:
- The thalamus acts as a relay station for sensory information (except for smell) and is involved in the processing of sensory input. However, it does not control motor functions directly; instead, it relays sensory information to the cerebral cortex, which then processes it and initiates motor responses. This statement is incorrect because the thalamus is primarily associated with sensory centers, not motor centers.

3. **Hypothalamus - Internal Environment Regulator**:
- The hypothalamus plays a crucial role in maintaining homeostasis by regulating various bodily functions such as temperature, hunger, thirst, and hormonal balance. This statement is correct.

4. **Cerebellum - Motor Coordination**:
- The cerebellum is essential for coordination, precision, and timing of movements. It helps in maintaining balance and posture. This statement is correct.

### Conclusion:
The mismatched option is **Thalamus - Motor and Sensory Centers**. The thalamus primarily deals with sensory information and does not control motor functions directly.

### Final Answer:
**Thalamus - Motor and Sensory Centers** is the mismatched option.

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