下列不是高血压的治疗目的及原则

A．减少致死性及非致死性并发症

B．控制于正常水平

C．根据高血压程度选用药物

D．根据并发症选用药物

E．剂量不需调整

BGP is an inter-autonomous system routing protocol; it is designed to be used between multiple autonomous ___40___. BGP assumes that routing within an autonomous system is done by an intra-autonomous system routing protocol. BGP does not make any assumptions about intra-autonomous system ___41___ protocols employed by the various autonomous systems. Specifically, BGP does not require all autonomous systems to run the same intra-autonomous system routing protocol.

BGP is a real inter-autonomous system routing protocol. It imposes no constraints on the underlying Internet topology. The information exchanged via BGP is sufficient to construct a graph of autonomous systems connectivity from which routing loops may be pruned and some routing. ___42___ decisions at the autonomous system level may be enforced.

The key feature of the protocol is the notion of Path Attributes. This feature provides BGP with flexibility and expandability. Path ___43___ are partitioned into well-known and optional. The provision for optional attributes allows experimentation that may involve a group of BGP ___44___without affecting the rest of the Internet. New optional attributes can be added to the protocol in much the same fashion as new options are added to the Telnet protocol, for instance.

41（）

A.routing 

B.switching 

C.transmitting 

D.receiving