—What is your sister doing ,Tom?

—She      at the mall. She    every Sunday.

A．shops,goes shopping

B．is shopping ,goes shopping

C．is shopping, is shopping

D．goes shopping,goes shopping

牙本质的反应性改变不包括（）

A.修复性牙本质

B.透明性牙本质

C.死区

D.骨样牙本质

E.继发性牙本质