<prompt> Insulinoma is the most common functioning tumor of-PancreasLiverGallbladderThyroid  <response>: Beta-cell tumours or insulinomas are the most common of pancreatic endocrine neoplasms . It may produce sufficient insulin to induce clinically significant hypoglycemia. Clinical picture is dominated by hypoglycemic episodes.,which occurs if blood glucose level falls below 50 mg DL of serum. Clinical manifestations are confusion,stupor and loss of consciousness. Ref:ROBBINS Textbook of pathology ref img 