男，18岁，Ⅱ、Ⅲ度烧伤60%，入院后第5天，病人体温下降明显，对周围淡漠，呼吸浅，脉搏细弱，白细胞及血小板较正常为低。创面停止生长、干枯，出现出血性坏死斑，提示为（）。

A.休克

B.蜂窝织炎

C.二重感染

D.烧伤创面脓毒症

E.全身感染

Carbon dioxide as a fire fighting agent has which advantage over other agents?（）.

A.It causes minimal damage

B.It is safer for personnel

C.It is cheaper

D.It is most effective on a per unit basis