Why Are Oral Antidiabetic Drugs Not Effective in the Management

Why are oral antidiabetic drugs not effective in the management of type 1 diabetes?

A) These drugs are too powerful to give to children.
B) Patients with type 1 diabetes do not produce insulin.
C) The oral drugs are less predictable in lowering blood glucose levels.
D) Patients with type 1 diabetes are more likely to have allergies to these drugs.