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: Physiology
Intron is not found in which DNA: 
Select and explain. 
A. Nuclear DNA, B. Mitochondrial DNA, C. B DNA, D. Z DNA
B: Mitochondrial DNA
Answer: B: Mitochondrial DNA 
Explanation: Mitochondrial DNA