Question: Ellis Island, the gateway for over 12 million immigrants to the United States as the nation's busiest immigrant inspection station and where social worker Ludmila Foxlee was employed from 1920 to 1937, was made part of which National Monument in 1965?
Sentence (from "Ellis Island Immigrant Hospital"): The hospital was one of the largest public health hospitals in United States history and is still viewed today as an extraordinary endeavor in the public health field.
Relevant evidence: No