What is the time complexity for finding a Hamiltonian path for a graph having N vertices (using permutation)?

What is the time complexity for finding a Hamiltonian path for a graph

1.	What is the time complexity for finding a Hamiltonian path for a graph having N vertices (using permutation)?
A.	O(N!)
B.	O(N! * N)
C.	O(log N)
D.	O(N)
Answer» C. O(log N)