**Core Concept**
The sixth cranial nerve (abducens) innervates the lateral rectus muscle, responsible for abduction of the eye. Palsy of this nerve impairs outward movement of the eye, leading to misalignment during gaze deviation.

**Why the Correct Answer is Right**
In a sixth nerve palsy, the left eye cannot abduct properly during left gaze. This creates a misalignment between the eyes, resulting in **diplopia (double vision)** specifically in the left gaze. The patient sees two images because the eye fails to move laterally. This is a classic clinical sign of abducens palsy, with diplopia occurring when looking to the left.

**Why Each Wrong Option is Incorrect**
Option A: **Accommodation paresis** is associated with third cranial nerve palsy (not sixth), affecting convergence and pupil constriction, not abduction.
Option B: **Ptosis** is due to third or fifth cranial nerve palsy, not sixth nerve involvement.
Option C: **Adduction weakness** is caused by third or fourth cranial nerve palsy, not the sixth. The sixth nerve controls abduction, not adduction.

**Clinical Pearl / High-Yield Fact**
Always remember: Sixth nerve palsy → **diplopia on left gaze** due to inability to abduct the eye. It is a classic example of **lateral rectus weakness** and is often seen in posterior fossa lesions or trauma.

✓ Correct Answer: D. Diplopia in left gaze