The proper answer to this question is option B "<span> Separation of Powers". Separation of powers is the three branch's of government which makes sure each branch doesn't get more powerful than the other.
I've done a bit of research on your question, and I have found that the answer is that he raised $1 billion dollars off of donors. I hope this is helpful. =]
The byzantine empire lost Rome. Rome was claimed by the byzantines in the 6th century and in the 6th century was given to the papacy as the major seat and capitol of the papal state