—How many people are still leading ____ life under ___ poverty line in the world?

—Perhaps one fourth.

A．a, the

B．a, a

C．不填，不填

D．the, 不填

直通列车异地票的预售期为（）天（特殊情况、动车组和直达列车除外）。

A.10

B.11

C.12

D.20