<prompt> Brain death is said to occur if there isAbsent spinal reflexesCortical death following widespread brain injuryAbsence of brainstem reflexesCore temperature of the body is below 35degC  <response>: C Absence of brainstem reflexes BRAIN DEATH is present when there is irreversible loss of all brain function, both brain-stem function cortical hemisphere function. Brain death criteria - Loss of brainstem function Absent cranial nerve reflexes - Pupillary light reflex; Corneal reflex; Oculoves-tibular reflex cold caloric test; No gag reflex. Absent respiratory brainstem reflexes is done by Apnea test: Loss of cortical function No spontaneous movement; no response to external stimuli; Irreversibility. Brain death is present when there is irreversible loss of brain function criteria-loss of brainstem function absent cranial nerve reflexes, pupillary light reflex, corneal reflex, oculovestibular reflex. 