This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: FMGE 2019, Subject name: Microbiology
[{'content': 'The causative agent for duodenal ulcer is; \nSelect and explain. \nA. Shigella, B. E. coli, C. H. Pylori, D. Lactobacilli', 'role': 'user'}, {'content': "Answer: C \nExplanation: H. Pylori is gram negative bacteria, non-spore forming, micro aerophilic, extra cellular bacteria. H. pylori causes Peptic ulcer disease (80% of duodenal ulcer and 60% of gastric ulcer) It acts by decreasing Somatostatin - producing D cells. Other diseases caused by it are - Chronic atrophic gastritis and Autoimmune gastritis Adenocarcinoma of stomach (non cardiac) and non-Hodgkin's gastric lymphoma H. pyloriinfection increases the risk of gastric malignancies such asgastric adenocarcinomaandMALToma's", 'role': 'assistant'}]