The accurate answer is option D that is time complexity for Kruskal's algo.
[ for adjacency list = O(ElogE), for matrix representation {at max E=V2} O(2*ElogV) ] Or (E*logV) or O (M*logN).
In general case or worst case we consider matrix representation so time complexity O (ElogV).
now coming to the question again
in worst case logN = O(N) so option B is also right O (M*N)
and since N = O(M) so option E is also right O (M2).