下列离子方程式正确的是（　　）

A．向Na₂CO₃溶液中加入过量CH₃COOH溶液 CO₃^2-+2H⁺=CO₂↑+H₂O

B．向Ca（HCO₃）₂溶液中加入过量的NaOH溶液：Ca²⁺+HCO₃^-+OH^-=CaCO₃↓+H₂O

C．等体积、等浓度的Ba（OH）₂稀溶液与NH₄HCO₃稀溶液混合：Ba²⁺+2OH^-+NH₄⁺+HCO₃^-═BaCO₃↓+NH₃•H₂O+H₂O

D．钠与CuSO₄溶液反应：2Na+Cu²⁺═Cu+2Na⁺

His mother hardly seemed to notice as the boy      go of her hand．

A．let

B．made

C．had

D．got