The answer is a.
Functional islet cell tumors of the pancreas secrete specific substances that result in several syndromes. Pancreatic gastrinomas (tumors of the G cells of the pancreas) secrete gastrin and are a cause of Zollinger-Ellison syndrome. This syndrome consists of intractable gastric hypersecretion, severe peptic ulceration of the duodenum and jejunum, and high serum levels of gastrin. The majority of gastri- nomas are malignant. Insulinomas (tumors of β cells) are the most common islet cell neoplasm and are usually benign. Symptoms include low blood sugar, hunger, sweating, and nervousness. Glucagonomas (islet cell tumors of the α cells) secrete glucagon and are characterized by mild dia- betes, anemia, venous thrombosis, severe infections, and a migratory, necrotizing, erythematous skin rash. δ cell tumors, which secrete somatostatin, produce a syndrome associated with mild diabetes, gallstones, steatorrhea, and hypochlorhydria. The majority of δ cell tumors are malignant. D1 tumors [also called vasoactive intestinal peptide tumors (VIPomas)] produce Verner-Morrison syndrome, which is characterized by explosive, profuse diarrhea with hypokalemia and hypochlorhydria. This combina- tion of symptoms is referred to as pancreatic cholera.