After the operation,my brother is now ______ on his feet and is living an active life.   [      ]

A. part          

B. down            

C. back            

D. up

某男，44岁。大面积烧伤后出现口渴，眼窝下陷，浅表静脉塌陷，皮肤弹性差，血压下降，脉搏细快，肢端湿冷。可能为

A．轻度等渗性缺水
B．中度等渗性缺水
C．轻度高渗性缺水
D．轻度低渗性缺水
E．中度低渗性缺水