This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General pathology, Subject name: Pathology
S 100 is a marker of ?- 
Select and explain. 
A. Melanoma, B. Schwannoma, C. Histiocytoma, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: Harshmohan textbook of pathology 7th edition. immunohistochemical stain for melanoma, schwannoma, histiocytoma is S 100. .