青年男性，突发头痛2小时，伴恶心、呕吐。体检：运动性失语，右侧肢体偏瘫，右瞳孔3mm，左瞳孔4mm，对光反射迟钝。下述处理哪项不正确（）

A.立即脑CT检查

B.静脉推注20％甘露醇250ml，同时做手术前准备

C.保持病人呼吸道通畅，防止窒息

D.若情况允许作脑血管造影

E.腰穿，脑脊液常规检查

For each blank, choose the best answer from the four choices and write down on the answer sheet.

(21) is a six bytes OSI layer 2 address which is burned into every networking device that provides its unique identity for point to point communication.

(22) is a professional organization of individuals in multiple professions which focuses on effort on lower-layer protocols.

(23) functions with two layers of protocols. It can connect networks of different speeds and can be adapted to an environment as it expands.

(24) is the popular LAN developed under the direction of the IEEE802.5.

(25) is the popular backbone technology for transmitting information at high speed with a high level of fault tolerance which is developed under the direction of ANSI.

（25）是（）

A.X.25

B.ATM

C.FDDI

D.SMDS