<prompt> Lesion in the optic chiasma causes -a Bitemporal hemianopiab Upper nasalc Lower nasald Upper temporale Lower temporalacdbdeadead  <response>: Central lesions of optic chiasmaCharacteristic visual field defect Bitemporal hemianopiaInitially temporal quadrantanopia may occur :-Lesion compressing from below upper temporalLesion compressing from above lower temporalLateral lesions of optic chiasma Binasal hemianopia 