168. A 62-year-old man has had anorexia, vomiting, and vague abdominal pain accompanied by weight loss of 6 kg over the past 2 months. An abdominal CT scan shows the stomach is shrunken with the gastric wall thickened to 1 cm and with extensive overlying mucosal erosions. Biopsy from lesion in the stomach is as shown below. Which of the following conditions most likely preceded development of his illness? a. Chronic alcoholism b. Hyperglycemia c. Pernicious anemia d. Gastro esophageal reflux