<span>In the European history, the Early Middle ages lasted from 5th to the 10th century. The Early Middle Ages was the period where population was declining, majority of which was from the urban centers. The trades were also decreasing, increasing the immigration. From this statement, D, B, A can be cancelled out.
The division of the Roman Empire into eastern and western halves was a crucial step in the formation of the "Byzantine Empire", since this Empire "grew" in many ways from the former.
