下列解释事实的离子方程式正确的是(    )

A．向明矾溶液中加入氢氧化钡溶液至沉淀质量最大Al³⁺+2SO₄^2-+2Ba²⁺+4OH^-=2BaSO₄↓+AlO₂^-+2H₂O

B．向Ca(HCO₃)₂溶液中加入过量NaOH溶液，有白色沉淀生成：Ca²⁺+HCO₃^-+OH^- =CaCO₃↓+H₂O

C．用惰性电极电解MgCl₂溶液：2Cl^-+2H₂O2OH^- +Cl₂↑+ H₂↑

D．NaClO溶液中通入少量的SO₂：ClO^-+H₂O+SO₂=Cl^-+SO₄^2-+2H⁺

They didn't go to bed          they finished their homework. [ ]

A.until

B.because

C.when

D.if