True.
And this is not only true for the distant and not so distant past, it's also true for the present as well. Slaves and prostitutes still exist around the world, despite us thinking that slavery may have been abolished. This is sadly not the case; in some areas in Africa and the Middle east, slavery still exists.
People would be in danger
This oddly sounds like something Hitler would have said, so based off my current knowledge of History, I will say it is answer choice D if what that is trying to say is communism.
Answer: barter
Explanation:
In trade, barter (derived from baretor) is a system of exchange where participants in a transaction directly exchange goods or services for other goods or services without using a medium of exchange, such as money.