Final answer:
The correct answer is option D. Native Americans.
Step-by-step explanation:
The ethnic group encouraged to migrate to California during the gold rush was D. recent Chinese immigrants seeking gold in California. These migrants arrived in large numbers, driven by the allure of the Gold Rush. During the mid-nineteenth century, the first Asian immigrants to the United States were predominantly Chinese men, drawn by the Gold Rush and later the construction of the Transcontinental Railroad.
However, this migration was met with significant resistance and racism, leading to severe discrimination against Chinese laborers. Over time, this culminated in the passing of the Chinese Exclusion Act of 1882, which barred Chinese individuals from immigrating to the U.S. and was a significant event in the history of Chinese Americans.