苷元-O-（6-去氧糖）_x-（D-葡萄糖）_y为（）

A．I型强心苷

B．Ⅱ型强心苷

C．Ⅲ型强心苷

D．次级强心苷

E．强心苷元

If you         for your favorite TV programs, you will feel sleepy.

A．stay up

B．set up

C．stay at

D．pick up