A mixture containing DNA fragments A, B, C, and D with molecular weights A + B = C, A > B and C < D was subjected to agarose gel electrophoresis. The position of these fragments from cathode to anode should be

As the information indicates that the largest DNA fragment to smallest ones are D, C, A and B. When the fragments are run in gel electrophoresis by loading in the wells at cathode that move towards anode, the largest one is present nearer to cathode and smallest one at the anode. Hence from cathode to anode the fragments that are trapped in the gel in a sequence are D, C, A and B.