Being afraid of falling behind the times, he has always been keeping himself ___ of the latest

development of technology.   [ ]

A. instructed    

B.  intended    

C.  informed  

D. demanded

下列一般不引起肺动脉高压的是（）

A.慢性缺氧

B.血黏度增加

C.左心功能不全

D.肺小动脉痉挛

E.肺血管阻力增加