OPTION C
In complete Graph with n vertices , each vertex has n-1 degree ,connecting to every other node.
In wheel Graph with n vertices , center vertex has n-1 degree & every other vertex has degree 3 , forming a cycle around center vertex.
For making a wheel Graph(n vertices) from Kn
Steps -
1) Chose center vertex (labeled) = nC1 (It can be anyone of n vertices)
2) make a cycle of remaining n-1 vertices = $\frac{(n-1)!}{2(n-1)}$
(this is similar to Round-Table arrangement of (n-1) people,considering clockwise &
anticlockwise same)
so, Total ways = nC1 * $\frac{(n-1)!}{ 2(n-1)}$ = $\frac{n!}{ 2(n-1)}$ = C(Ans)