Which cranial nerve pairs are purely motor and control eye movement? B) I, VIII, XI C) III, III D) \( I V, V I . V I I \)

To determine which cranial nerve pairs are purely motor and control eye movement, let's analyze the options provided: 1. **Cranial Nerve III (Oculomotor Nerve)**: This nerve is primarily responsible for controlling most of the eye's movements, including the constriction of the pupil and maintaining an open eyelid. It is a motor nerve. 2. **Cranial Nerve IV (Trochlear Nerve)**: This nerve controls the superior oblique muscle, which is responsible for downward and lateral eye movement. It is also a motor nerve. 3. **Cranial Nerve VI (Abducens Nerve)**: This nerve controls the lateral rectus muscle, which is responsible for abducting the eye (moving it laterally). It is a motor nerve as well. Now, let's evaluate the options: - **B) I, VIII, XI**: - I (Olfactory) is sensory. - VIII (Vestibulocochlear) is sensory. - XI (Accessory) is motor but does not control eye movement. - **C) III, III**: - This option seems to be a typographical error since it lists the same nerve twice. However, if it refers to cranial nerve III (Oculomotor), it is a motor nerve controlling eye movement. - **D) I V, V I . V I I**: - This option seems to be a misrepresentation of the cranial nerves. If it refers to IV (Trochlear), VI (Abducens), and VII (Facial), then: - IV (Trochlear) is motor and controls eye movement. - VI (Abducens) is motor and controls eye movement. - VII (Facial) is primarily a motor nerve for facial expressions but does not control eye movement. Based on this analysis, the correct answer that includes purely motor cranial nerves controlling eye movement is: **C) III, III** (assuming it refers to the Oculomotor nerve). If we consider the correct cranial nerves controlling eye movement, the complete answer should include III, IV, and VI. However, since none of the options explicitly list all three, C is the closest correct answer.