Question

Which civilization had the most influence on the structure of the U.S. government?

India
China
Rome
Egypt

Answer 1

China wasn't even close to influence anything. Same for Egypt. India was a conquered country, so it was being the one being influenced.

The answer is Rome

Romans were dominating the whole Europe before England emerged to colonize other lands and even England was, obviously, influenced by the Roman legacy.

It is from Roman law that comes the division between public law and private law, for example.

Answer 2

Rome civilization had the most influence on the structure of the U.S. government
Roman law developed the division between public law, in which the state is directly involved, such as with issues of treason and taxation, and private law, concerned with disputes between people, such as over contracts.
When the Bishop of Rome took power after Constantinople (now Istanbul ) became the capital of the empire, ideological differences became manifest between the East and West. Eastern Christians looked more readily to Constantinople , its Emperor and its bishop.