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: Surgery
The following statement about keloid is true ? 
Select and explain. 
A. They do not extend into normal skin, B. Local recurrence is common after excision, C. They often undergo malignant change, D. They are more common in whites than in blacks
B: Local recurrence is common after excision
Answer: B: Local recurrence is common after excision 
Explanation: Ans. is 'b' i.e., Local recurrence is common after excision