One Consequence of the Collapse of the Western Roman Empire

One consequence of the collapse of the western Roman empire in Europe was that

A) Latin ceased to be a commonly spoken language, and Germanic languages spread widely.
B) populations that had converted to Christianity reverted back to their polytheistic roots.
C) Arab invaders conquered much of Europe with relative ease following the Roman collapse.
D) Slavic populations ascended as the most powerful force in Europe.