What are the units of Equilibrium equations $K_p$ and $K_c$ when $\Delta n_g < 0$ respectively ?

Question

(a) $(atm)^{\Delta n_g} , (L mol^{-1})^{\Delta n_g}$

(b) $(atm)^{\Delta n_g} , (mol L^{-1})^{\Delta n_g}$

(c) $(atm) , (L)^{\Delta n_g}$

(d) $(atm) , (L mol^{-1})^{\Delta n_g}$