Answer: c. all followed Arianism.
Step-by-step explanation:
All the kingdoms of the Vandals, Visigoths, and Ostrogoths were Germanic tribes that migrated into the Western Roman Empire and established their own kingdoms. They had a similarity with the people of the Western Roman Empire whom they conquered in that they all followed Arianism.
Arianism is a form of Christianity that believes that Jesus Christ is not fully God, but rather a created being. This doctrine was rejected by the Catholic Church, which was dominant in the Roman Empire, and it was one of the main reasons for the division between the Catholic and Arian Christians.
It's worth noting that many of the Germanic tribes that invaded the Roman Empire were Arian Christians, and this religious affiliation played a significant role in their interactions with the Roman population. They were able to establish alliances with some of the Arian-leaning segments of the population, which helped them to gain control over many of the Western Roman provinces.