．The highest award was given to Anna, who _____ so hard on the project for years, and at last her efforts paid off.

A．has worked

B．worked

C．was working

D．had been working

蛛网膜下腔出血的主要CT表现是()

A．三脑室呈高密度影

B．侧脑室呈高密度影

C．外侧裂池见高密度影

D．基底节区见高密度影

E．枕叶见高密度影