If these permutations were in a line, then the equation would be n!. But since we are dealing with a circle, it's a little bit different, given that there is no specific beginning or end. This means that you could rotate the circle around n different ways and still have the same circular permutation. Thus, this would be the expression you are looking for:
n!/n, which can be simplified as (n-1)!
The correct answer is the second option.
