G1 and G2 are two graphs as shown:
Planar Graph :- A planar graph is a graph that can be embedded in the plane, i.e., it can be drawn on the plane in such a way that its edges intersect only at their endpoints. In other words, it can be drawn in such a way that no edges cross each other.
Here only G2 is planar graph.
Hence,Option(D)G1 is not planar and G2 is planar.
why G2 is not planar ?