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
Which of the following is the best morphological feature to distinguish ulcerative colitis from crohn's disease ? 
Select and explain. 
A. Pseudopolyps, B. Crypt abscesses, C. Lymphoid aggregates, D. Mucosal edema
A: Pseudopolyps
Answer: A: Pseudopolyps 
Explanation: Pseudopolyps are hallmark of ulcerative colitis and is the best morphological feature to distinguish between the two.