An undirected graph G has n nodes. Its adjacency matrix is given by an n × n square matrix whose (i) diagonal elements are 0‘s and (ii) non-diagonal elements are 1‘s. which one of the following is TRUE?
1) Graph G has multiple spanning trees of different costs
2) Graph G has multiple distinct MSTs, each of cost n-1
3) Graph G has a unique MST of cost n-1
4) Graph G has no minimum spanning tree (MST)