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
Best site for taking biopsy for viral oesophagitis is 
Select and explain. 
A. Edge of ulcer, B. Base of ulcer, C. Adjacent indurated area around ulcer, D. Surrounding normal mucosa
A: Edge of ulcer
Answer: A: Edge of ulcer 
Explanation: . Edge of ulcer