Which statement(s) best describe the Persian empire? Select the two correct answers. A.
It conquered most of what is now known as Western Europe.

B.
It created a postal system that used horsemen as messengers.

C.
It established a highly skilled professional army built around elite units.

D.
It forced conquered peoples to adopt Persian customs and religious beliefs.

E.
It was the oldest and smallest of the ancient Mesopotamian empires.