This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Enzymes, Subject name: Biochemistry
All are true about nohern blotting technique except 
Select and explain. 
A. Involves electrophoresis, B. Requires hybridization probes, C. Used to detect DNA molecules, D. Requires restriction endonucleases
C: Used to detect DNA molecules
Answer: C: Used to detect DNA molecules 
Explanation: The nohern blot is a technique used in molecular biology research to study gene expression by detection of RNA (or isolated mRNA) in a sample. A general blotting procedure stas with extraction of total RNA from a homogenized tissue sample or from cells. Eukaryotic mRNA can then be isolated through the use of oligo (dT) cellulose chromatography to isolate only those RNAs with a poly(A) tail.RNA samples are then separated by gel electrophoresis. Since the gels are fragile and the probes are unable to enter the matrix, the RNA samples, now separated by size, are transferred to a nylon membrane through a capillary or vacuum blotting system. Capillary blotting system setup for the transfer of RNA from an electrophoresis gel to a blotting membrane.