## **Core Concept**
The sixth cranial nerve, also known as the **abducens nerve**, is responsible for the motor innervation of the **lateral rectus muscle**. This muscle is crucial for **abduction of the eyeball**, which is the movement of the eye away from the midline of the body.

## **Why the Correct Answer is Right**
The abducens nerve (CN VI) controls the lateral rectus muscle. When this nerve is affected, as in the case of a sixth nerve palsy, the patient experiences difficulty in moving the affected eye outward, leading to **impaired abduction**. This results in the inability to properly move the eye away from the nose. In the context of the question, the left-sided sixth nerve palsy would lead to an inability to abduct the left eye.

## **Why Each Wrong Option is Incorrect**
- **Option A:** This option is not provided, but typically, incorrect options might suggest other ocular movements or conditions not directly related to the function of the abducens nerve.
- **Option B:** Similarly, without the content, we can infer that any option suggesting a different ocular muscle involvement or an unrelated condition would be incorrect based on the specific role of CN VI in eye movement.
- **Option C:** This would be incorrect if it suggested a different cranial nerve palsy or an unrelated condition, as the specific deficits correlate with the nerve affected.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that the **sixth cranial nerve (abducens nerve) has a long intracranial course**, making it particularly susceptible to damage from **increased intracranial pressure**. This is why sixth nerve palsy can be an early sign of raised intracranial pressure, as seen in this patient with metastases.

## **Correct Answer:** . Impaired abduction of the left eye.