Final answer:
The cranial nerve that lies directly anterior to the optic chiasm is Cranial Nerve III (Oculomotor Nerve).
Step-by-step explanation:
The cranial nerve that lies directly anterior to the optic chiasm is Cranial Nerve III (Oculomotor Nerve). The oculomotor nerve is responsible for controlling the movement of most of the eye's muscles, including the superior rectus, inferior rectus, medial rectus, and inferior oblique muscles. It also regulates the size of the pupil and controls the shape of the lens for focusing.