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: Dental
Teeth which can't be used as abutment: 
Select and explain. 
A. Endodontically treated teeth, B. Pulp capped teeth., C. Both, D. None
B: Pulp capped teeth.
Answer: B: Pulp capped teeth. 
Explanation: None