Only by increasing the number of doctors by 50 percent ________ properly in this hospital.

A．can be the patients treated

B．can the patients be treated

C．the patients can be treated

D．treated can be the patients

水生花卉、湿生花卉、中生花卉、早生花卉都是根据花卉对（）的不同要求而分类的。

A.温度

B.光照

C.空气

D.水分