Fast please

- Coefficient of 1/x in the expansion of (1 + x)"(1 + 1/ x)" is n! 2n! (a) (b) (n-1)!(n + 1)! (n-1)!(n +1)! n! 2n! (c) (d) (2n-1)!(2n + 1)! (2n-1)!(2n + 1)! - 52