Which of the following is true about the Adjacency Matrix representation of graphs?

n: number of vertices

m: number of edges

a$.$ Space requirement for adjacency matrix is Theta$($m $^2)$

b$.$ Space requirement for adjacency matrix is Theta $($n $+$ m$)$

c$.$ Space requirement for adjacency matrix is Theta $($ n $*$ m$)$

d$.$ Space requirement for adjacency matrix is Theta $($n $^2)$