How did Constantinople and the Byzantine empire grow powerful ?
A: it was isolated and have special treatment to its own traders
B: the Byzantine empire had a strong army and excellent rulers who were both popular and wise
C: it was located at a crossroads of major land and sea routes
D: duties on trade goods gave it great wealth, and diversity of people and ideas that entered the city made it an international center of trade an culture
E: b, c, and d