A - Most immigrants left Ellis island very quickly
A is the correct answer as those who entered through Angel Island on the West Coast were detained for weeks and typically from Asian countries.
B is incorrect as those who came through Angel Island soon required to have relatives in America, those who didn't were turned away.
C is incorrect as most immigrants processed at Ellis island were legally allowed to enter.
D is incorrect as it is only recorded that those with medical issues at Ellis island were turned away.
Hope this helps!