This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
Typhoid ulcer is - 
Select and explain. 
A. Ulceration of the Peyer's patch, B. Longitudinal ulcer, C. May perforate, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: All of the above