Final answer:
The ease of travel around the Roman Empire greatly contributed to the spread of Christianity by facilitating the movement of peoples and the dissemination of ideas and religions.
Step-by-step explanation:
Which feature of the Roman empire most contributed to the spread of Christianity?
The correct answer is D. the ease of travel around the empire. The ease of travel around the Roman Empire, facilitated by extensive road networks and safe seas under Roman control, played a vital role in the spread of Christianity. It allowed not only for the movement of peoples but also for the dissemination of ideas and religions.