What did the hellenistic kings build in conquered lands?

By the time he died 13 years later, Alexander had built an empire that stretched from Greece all the way to India. ... It lasted from the death of Alexander in 323 B.C. until 31 B.C., when Roman troops conquered the last of the territories that the Macedonian king had once ruled.

the answer should be a. the sui empire, the tang empire extended from korea in the west to manchuria in the east.