A 57-Year-Old Man Is Being Examined by His Physician Due

A 57-year-old man is being examined by his physician due to complaints of frequent gnawing and burning pain in the middle and upper stomach occurring between meals and most acutely at night. Additional symptoms reported by the patient include heartburn, black stools, and on occasion seeing that his vomit looks like coffee grounds. You suspect the patient is suffering from a peptic ulcer. A defect in which of the following cells in the gastrointestinal tract would most likely be expected given this diagnosis?

A) chief
B) enterochromaffin-like (ECL)
C) enteroendocrine L cells
D) gastric mucus cells
E) parietal