Correct option: Concentration of DNA
Explanation: Electrophoresis shows bands which validates the presence of protein or DNA or RNA in the sample being run. Therefore, option A is a correct statement. Again, electrophoresis works on the principle of separating the molecules in the basis of the sizes, so option B is also a correct statement. The thickness of the agarose gel band, can tell about the presence of a dimer, so option C is also correct. The only thing in the above options which can't be predicted by agarose gel electrophoresis is the concentration of DNA because it doesn't work on the principle of quantity of the sample, but on the size of the sample molecules.
