If all the persons are arranged alphabetical order in

Solution

M sits opposite to the one who sits third to the left of G.  Either M or G is sitting at the end of the row. From the above condition, there are two possibilities.  Only one person sits between M and N. The number of persons sitting to the left of N is the same as to the right of R. From the above condition, there are three possibilities. Only two persons are sitting between R and the one who sits opposite to A. The number of persons who sits between A and N is the same as between V and S. V and R are not immediate neighbors.  D sits to the right of E and does not face A. From the above condition, case1 and case2a get eliminated. Case-2  K sits to the left of L and to the right of J. From the above condition, case2 shows the final arrangement.