This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: G.I.T, Subject name: Pathology
[{'content': 'Specific for GIST tumor is - \nSelect and explain. \nA. CD117, B. CD29, C. CD34, D. CD23', 'role': 'user'}, {'content': 'Answer: A \nExplanation: About 80% of all GISTs have oncogenic,gain of function mutations of the gene coding the tyrosine kinase c-KIT or CD117 GENERAL AND SYSTEMIC PATHOLOGY RAMDAS NAYAK PAGE NO:390', 'role': 'assistant'}]