II. if an edge (u,v) is contained in some minimum spanning tree, then it is a light edge crossing some cut of the graph.
III. If (u,v) is a light edge connecting CC(connected component) to some other component in the forest of graph G, then (u, v) is included in the minimum spanning tree.
didn’t understand the part “light edge crossing some cut of the graph”
can someone explain me with the diagram ??