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
To prevent dislodgement of abutment in distal extension RPD, it is required to have a: 
Select and explain. 
A. Positive denture base - tissue relationship, B. Stress breaker, C. Indirect retainer, D. Multiple clasping
A: Positive denture base - tissue relationship
Answer: A: Positive denture base - tissue relationship 
Explanation: None