Assertion : All motor neurons nerve impulses from the spinal cord to the brain.
Reason : Motor neurons conduct nerve impulses from the spinal cord to motor centres of brain.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion.
B. If both assertion and reason are true but reason is not the correct explanation of assertion.
C. If assertion is true but reason is false.
D. If both assertion and reason are false.

Answer

To solve the question regarding the assertion and reason, we need to analyze both statements carefully.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "All motor neurons carry nerve impulses from the spinal cord to the brain."
- This statement is incorrect because motor neurons (efferent neurons) actually carry impulses from the brain to the spinal cord and then to the muscles or glands, not the other way around.

2. **Understanding the Reason**:
- The reason states that "Motor neurons conduct nerve impulses from the spinal cord to motor centres of the brain."
- This statement is also incorrect. Motor neurons do not carry impulses to the brain; they carry impulses away from the brain to effectors (muscles or glands).

3. **Conclusion**:
- Since both the assertion and the reason are false, we can conclude that the correct answer to the question is that both statements are false.

### Final Answer:
Both the assertion and reason are false statements.