Read the following statements carefully and choose the option including correct statements only (a) cranial nerves are motor in nature. (b)Lumbar plexus innervates chest and arms. (c) Lateral movements of eye are controlled by 3rd cranial nerve. (d)Cauda equina is a bunch of only cranial nerves which exit at the level of last sacral vertebra.

Options

A. (b) & (d)
B. (a) & (b)
C. (a) & (c)
D. (b) & (C)

Answer

To solve the question, we need to evaluate each statement one by one to determine if they are correct or incorrect.

### Step-by-Step Solution:

1. **Evaluate Statement (a)**: "Cranial nerves are motor in nature."
- **Analysis**: Cranial nerves can be motor, sensory, or mixed (containing both motor and sensory fibers). Therefore, this statement is **incorrect**.

2. **Evaluate Statement (b)**: "Lumbar plexus innervates chest and arms."
- **Analysis**: The lumbar plexus primarily innervates the lower limbs and parts of the pelvis. It does not innervate the chest and arms, which are innervated by the brachial plexus. Therefore, this statement is **incorrect**.

3. **Evaluate Statement (c)**: "Lateral movements of the eye are controlled by the 3rd cranial nerve."
- **Analysis**: The lateral movement of the eye is primarily controlled by the abducens nerve (6th cranial nerve), not the 3rd cranial nerve (oculomotor nerve), which controls most eye movements and pupil constriction. Therefore, this statement is **incorrect**.

4. **Evaluate Statement (d)**: "Cauda equina is a bunch of only cranial nerves which exit at the level of the last sacral vertebra."
- **Analysis**: The cauda equina is a collection of spinal nerve roots (not cranial nerves) that extend from the lower end of the spinal cord. It does not consist solely of cranial nerves and is not limited to the last sacral vertebra. Therefore, this statement is **incorrect**.

### Conclusion:
After evaluating all four statements, we find that all of them are incorrect. Thus, the correct option including only correct statements is none of the provided options.