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: Pathology
Which of the following is true about autosomal dominant: 
Select and explain. 
A. Variable age of onset, B. Reduced penetrance, C. Variable expressibility, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: Autosomal dominant disorders:

Variable age of onset.
Reduced penetrance.
Variable expressibility.