Using the following lemma :
If G is a finite graph and simple. By adding an edge, then one and only one of these two folowings is happen:
1. A circle in graph is closed (a circle that never had before)
2. Connectivity elements is now 1 less than before.
If G is a graph(simple graph) with n vertexes then:
G connective minimal graph==>G without circles and have n-1 edges.