Final answer:
The feature of the Roman Empire that continued in the Byzantine Empire was b. Christianity as the main religion, which remained foundational throughout its history.
Step-by-step explanation:
What feature of the Roman Empire continued in the Byzantine Empire? The feature that persisted was Christianity as the main religion. Although the Byzantine Empire, also known as the Eastern Roman Empire, selected Greek as its official language, it maintained the Christian religion as a cornerstone of its identity and governance. Throughout its existence, after the fall of the Western Roman Empire, the Byzantine Empire spread Christianity extensively to all corners of its territories, influencing regions such as Egypt and Syria to become major Christian centers with a Greek-speaking educated class. This adoption and spread of Christianity by the Byzantine Empire played a critical role in preserving and shaping the cultural and religious landscape of Europe and the Near-East, long after the empire's eventual decline.