<prompt> True about Type I diabetes melitus is ?Autoimmune disorderInsulin non-dependentInsulin does not improve the symptomsLate age of onset  <response>: Type 1 DM results from T cell mediated auto-immune destruction of the insulin secreting beta cells in the pancreatic islets and insulin deficiency. This autoimmune process is thought to be triggered by an infectious or environmental stimulus in genetically susceptible individuals. It can develop at any age, develops most commonly before 20 years of age. Thus it is insulin dependant and insulin improves the symptoms. Reference : page 803 Davidsons Principles and practice of Medicine 22nd edition and page 2403 Harrisons Principles of Internal Medicine 19th edition 