Which of the following mixtures will act as a buffer solution when dissolved in 50 mL of water?

Question

(a) 0.2 mol of aniline + 0.2 mol of HCl

(b) 0.2 mol of aniline + 0.4 mol of NaOH

(c) 0.2 mol of NaCl + 0.1 mol of HCl

(d) 0.2 mol of aniline + 0.1 mol of HCl