下列各组溶液,只用组内物质不能鉴别的是( )
A:NaNO3 KCl Na2CO3 HCl
B:HCl Na2CO3 K2SO4 BaCl2
C:MgSO4 KOH KNO3 CuSO4
D:KOH MgCl2 H2SO4 NaCl
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