Assertion : Type I diabetes is caused by destruction of cells of Islets of Langerhans. Reason : Insulin can be taken as injections by Type I patients.

Step-by-step solution

Type I diabetes is an autoimmune disease wherein immune system destroys cells in pancreas called beta cells which make insulin. Insulin is a hormone that helps move sugar from blood into body tissues where cells use it as fuel. Damage to beta cells leads to build up of sugar in blood as cell are not able to utilise it which leads to high blood sugar. Patients having type I diabetes take insulin injections to control blood sugar.