Question

A non-planar graph with minimum number of vertices has

• A. 9 edges, 6 vertices
• B. 6 edges, 4 vertices
• C. 10 edges, 5 vertices
• D. 9 edges, 5 vertices

Answer 1

The correct option is C 10 edges, 5 vertices

$K_5$ is smallest non-planar graph in terms of number of vertices.
The number of vertices in $K_5$ is 5 and number of edges in $K_{5}is\frac{5\times 4}{2}=10.$