With China's policy of reform and opening to the outside world, the city has had________growth in the

number of international tourists over the past two decades.[ ]

A. abstract  

B. solid  

C. fragile  

D. steady

下列哪项浓度高者有益（）

A．极低密度脂蛋白(VLD

B．低密度脂蛋白(LD

C．乳糜微粒

D．高密度脂蛋白(HD

E．ApoB