Answer
The problems the church faced during the invasion of the magyars and vikings include:
1. Simony: This involves selling church properties and sacred items.
2. Lay investiture: This deals with appointment of religious leaders by traditional rulers
3.Clerical marriage: Allowing clergymen to marry and it is different from allowing married men become clergy.
4.Celibacy: Abstaining from intimate activities.
5.Abuse of power in the hands of lay rulers.
