Which of the following is correct?
(A) In directed graph sum of length of all adjacency list is $|E|$
(B) The adjacency matrix requires $O(V^2)$ memory
(C) In an undirected graph the sum of length of all adjacency list is $|E|$
(D) The memory requirement of adjacency list depends on number of edges in graph
(a) A, B, C
(b) B, C, D
(c) A, B, D
(d) A, C, D