Mainly from Europe more specifically Germany ,Ireland, England and France due to various problems such as crop failure. They have also immigrated because of Christopher Columbus's voyages of the new world.
Black holes themselves can not be seen, nor do they leave trails (since emptiness does not have to be caused by a black hole), but there is evidence for black holes: scientists can see the effects of their gravity on nearby stars. The answer is B.
He was known for his code of laws called Code of Hamurabbi.
