— How can I tell one tree from another? 

— You can mostly tell them by the ______ of their leaves.  [ ]

A. shape

B. size

C. age

D. color

下列关于高血压降压治疗的原则，哪一项是错误的（）

A.发生高血压急诊应迅速降压

B.血压控制满意后，可立即停药

C.单个药物宜从小剂量开始

D.联合用药

E.尽可能用长效制剂，减少血压波动