下列溶液用酸碱滴定法能准确滴定的是()
(A)0.1mol/LHF(pKa=3.18)
(B)0.1mol/LNaAc[pKa(HAc)=4.74]
(C)0.1mol/LNH4Cl[pKb(NH3)=4.75]