Answer:
C. Many Americans held nativist or racist views.
Step-by-step explanation:
Angel Island is the largest natural island that is located in San Francisco Bay and it was used as a military fort, immigration inspection and detention facility and a quarantine station.
With the introduction of the Chinese Exclusion Act of 1882, the government of the United States of America restricted a group of immigrants with respect to their nationality, class and race. Thus, by virtue of the passage of this law, all immigrants from China were examined by the immigration authorities or customs officials.
Hence, the statement which best explains why the US government placed restrictions on Asian immigration through Angel Island was that, many Americans held nativist or racist views.