B. Immigrants left Ellis Island within hours; they often remained in Angel Island for weeks.
Immigrants in Angel Island came from Asian countries, specifically, China, Japan, Russia, and South Asia. Upon arriving in Angel Island, they have to undergo medical examination and interrogation process.
The length of time an immigrant spend on Angel Island varies on the length of his or her interrogation process. Some immigrants produce false paperwork, which lengthened their interrogation process because the authenticity of said paperwork must be verified before they can be granted entry to the United States.