B

Benzodiazepines have a much wider therapeutic index than older sedative-hypnotics such as barbiturates, so accidental or intentional ingestion of large amounts rarely causes life-threatening coma or respiratory arrest, making them markedly safer in overdose compared with other sedatives [Gaudreault, 1991, PMID 1888441; Sellers, 1978, PMID 26460]. Options A, C and D are incorrect because benzodiazepines distort normal sleep architecture less than barbiturates, do not enhance hepatic drug metabolism, and several agents (e.g., lorazepam, oxazepam) lack active metabolites.