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: Biochemistry
When one strand of DNA isolated showed 20A, 25G, 30C, 22T. How many A, G, C, T will be there in both strands together 
Select and explain. 
A. A=45 G=45, C=52, T=52, B. A=50, G=47, C=50, T=47, C. A=44, G=55, C=55, T=44, D. A=42, G=55, C=55, T=42
D: A=42, G=55, C=55, T=42
Answer: D: A=42, G=55, C=55, T=42 
Explanation: Chargaff's rule