<prompt> True statement regarding delirium includesInsidious onsetClear consciousnessIrreversibleDecreased attention  <response>: D Decreased attention DELIRIUM: Delirium is defined as a transient, usually reversible, cause of cerebral dysfunction and manifests clinically with a wide range of neuropsychiatric abnormalities. Clinical hallmarks are decreased attention span and a waxing and waning type of confusion. Delirium or acute confusional state is a transient global disorder of cognition. 