What Is the Basic Underlying Pathology of Diabetes Mellitus

What is the basic underlying pathology of diabetes mellitus?

A) Failure of insulin production or of insulin binding to its receptors
B) Loss of the ability for insulin to convert body fat into carbohydrates or glucose
C) Inability of pancreatic insulin to break down glycogen during periods of fasting
D) Loss of the ability of pancreatic insulin to process carbohydrates for intestinal elimination,resulting in excessively high blood glucose levels