Which muscle is associated with the movement of the eye to the left?

The medial rectus muscle plays a critical role in moving the eye to the left. This muscle is one of the extraocular muscles that control eye movement and is specifically responsible for adduction, which means it pulls the eye inward toward the nose. When the left eye moves to the left, the medial rectus of the left eye contracts, allowing for that lateral movement.

In contrast, the lateral rectus muscle is responsible for moving the eye outward or laterally, which would be the opposite movement. The superior rectus and inferior oblique muscles are primarily involved in vertical movements and also assist with some rotational movements of the eye, but they do not specifically contribute to the leftward movement. Therefore, the role of the medial rectus in adducting the eye towards the nose makes it the correct answer for this question.