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: Pharmacology
Pharmacogenetics is associated with: 
Select and explain. 
A. Variability of enzyme action, B. Individual variability in oral absorption, C. Different DRC in different individuals, D. All of these
D: All of these
Answer: D: All of these 
Explanation: None