What Was the "Continuous Passage" Rule of 1908

What was the "continuous passage" rule of 1908?

A) a government policy distinguishing between visible minorities and those who could "pass" for being white
B) a law that permitted South Asian immigration only on ships that made non-stop trips from India
C) a law regulating Chinese workers on the railway,which allowed them free travel as long as they made non-stop trips to their destination
D) an immigration policy that prevented any visible minorities from entering Canada,and restricted them to continuous passage through Canada to another destination