在一定温度下，R的二价硫酸盐的饱和溶液的溶质质量分数为20%，现加入该无水盐1.0克到该饱和溶液中，析出带7分子结晶水的晶体2.3克．该硫酸盐的化学式为（　　）

A．CuSO₄

B．ZnSO₄

C．FeSO₄

D．Na₂SO₄

—My grandmother died last night. I'm very sad about it. 

—________. [ ]

A. You' re welcome          

B. That's right  

C. I 'm very sorry to hear that  

D. I hope you 'll feel better soon.