This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Metabolism of nucleic acids, Subject name: Biochemistry
DNA restriction fragments are separated by 
Select and explain. 
A. Paper chromatography, B. Agarose gel electrophoresis, C. Thin-layer chromatography, D. Ultracentrifugation
B: Agarose gel electrophoresis
Answer: B: Agarose gel electrophoresis 
Explanation: Typically, a DNA molecule is digested with restriction enzymes, and the agarose gel electrophoresis is used as a diagnostic tool to visualize the fragments. An electric current is used to move the DNA molecules across an agarose gel, which is a polysaccharide matrix that functions as a so of sieve. Ref-D.M.Vasudevan 7/e p479