Why was the Byzantine Empire formed? What do you think had the most to do with the decline of the Byzantine Empire?

The byzantine empire started when in 330 A.D., Roman Emperor Constantine I chose Byzantium as the site of a “New Rome” with an eponymous capital city, Constantinople. The decline of the Byzantine Empire was the Crusades. The Crusades were a series of military campaigns organized by Christian powers to retake the holy land Jerusalem from Muslim Control. Thousands of people died.

given all the practice it takes to become proficient at writing up ncoer's, , awards, and conselings as well as learning how to become a well rounded   leader , and managing different types of people

i think it's b or c hope this