<s>[INST] context: Subcoical centre for lateral/horizontal conjugate gaze lies in the abducent nucleus In pons, though some authors take it to be PPRF (para-median pontine reticular formation) and others as nucleus prepositus hypoglossi. This centre receives input from the contralateral frontal eye field and moves ipsilateral lateral rectus and contralateral medial rectus muscle projections of MLF (medial longitudinal fasciculus) PPRF lesion leads to inactivity of saccadic movements by lateral rectus and contralateral medial rectus. There is loss of horizontal saccades directed towards the side of the lesion but pursuit and vergence movements are preserved. One and a half syndrome: Unilateral abducent and bilateral MLF lesion. On attempted lateral gaze, the only muscle functional is the intact lateral rectus. MLF connects the nuclei controlling eyeball muscles--(LR6 SO4)3 and mediates nystagmus and lateral conjugate gaze. Its fibers originate in vestibular nucleus and terminate in abducent, trochlear and oculomotor nuclei. It coordinates eyeball movements with the head. Trochlear nucleus is concerned with veical gaze movements. Nucleus prepositus hypoglossi (and not hypoglossal nucleus), is involved in the gaze circuitry. [/INST] question: Final center for horizontal movements of the eye is | options: A: Abducent nucleus B: Irochlear nucleus C: Oculomotor nucleus D: Vestibular nucleus | answer: A </s>