What is the main reason that rome was built on hills? a. the hills had fertile farmland. b. the hills provided a natural defense. c. the hills were near a port. d. the hills were densely populated.

B.The hills provided a natural defense. The more defense u have the better ^-^

B. The hills provide a natural defense

Hope it helps; Pls mark as brainliest

just finished this it is b. centrifugal force

necessary and proper clause. the congress shall have power to all laws which shall be necessary and proper for carrying into execution the foregoing powers, and all other powers vested by this constitution in the government of the united states, or in any department or officer thereof.