Which of these statements is true about u. s. constitution?

The oldest constitution still in use is the Constitution of San Marino established in 1600; nearly two centuries before the US constitution. and The US Constitution was inspired in part by the Magna Carta, but is very different in format and detail.

Thomas Jefferson was not a delegate to the Constitutional Convention which wrote the US Constitution; at the time he was the US Ambassador to France so had no part in writing that document.. 

b

explanation:

the northwest ordinance of 1787 guaranteed basic rights for settlers and banned slavery there.