Question

a lesion to the abducens nerve (cn 6) causes difficulty with which eye movement?
abduction
adduction
elevation
depression

Explanation:

The abducens nerve (CN 6) innervates the lateral rectus muscle. The lateral rectus muscle is responsible for abduction of the eye (moving the eye outward away from the mid - line). A lesion to CN 6 would impair the function of the lateral rectus muscle, leading to difficulty with abduction.

Answer:

A. Abduction