Answer:
C. In the ancient world, Rome was the center of a powerful empire.
However, it gradually lost its strength, and in 410 CE it was
invaded and practically destroyed. What factors contributed to
Rome's downfall? Why did it find itself unable to defend its own
walls?
Step-by-step explanation:
The first question asks what the cause of Rome's downfall was. In the second sentence the effect is Rome was invaded and destroyed.