first should know that this is the fundus or body of the gastric, so it should be the parietal cell domaine; then think the mucus is the protective one , A without hesitate. then the other on the upper glandular layer should be the paretal cell, which is B. others like C is so small ,in the deeper glandular layer and basalphilic looking maybe is the chief cell . then deeper could be the submucosa layer. UW ID124 fyi.
Burning Abdominal Pain that occurs hours after eating = Gastric Ulcer
Sweating profusely and orthostatic hypotension
Epigastric tenderness
2-cm mass = most likely a GASTRINOMA\
This is confirmed by the question stating the tumor cells release gastrin but requires you to understand what parietal cells and basic gastric mucosal histology looks like
REFERENCE: ZOLLINGER-ELLISON SYNDROME
submitted by โbingcentipede(359)
Good explanation on reddit: https://www.reddit.com/r/step1/comments/d8aqj5/spoiler_nbme_16_hey_can_anybody_advice_how_to_get/
Essentially, A = mucinous glands (foamy cytoplasm) B = parietal cells (stain eosinophilc, P ar I etal cells stain PInk w/ a fried egg appearance. Additionally, they're above chief cells C = chief cells (stain basophilic, super dark, and below parietal cells)