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
Consider the following factors regarding the placement of R.P.D, which of the following determine the path of placement? 
Select and explain. 
A. Guiding planes, B. Retentive areas, C. Interferences, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: None