The policy that favored people born in the United States during the early 1900s was called

The correct answer is: The American System.

Explanation:

The American system was en economic plan made in the 19th century and it consisted of three important parts: to protect and foster American industry, to introduce a protective Tariff in order to facilitate to the nation to raise money from the taxes and to protect nation's good from cheaper foreign items.

The main objective of the American system was to improve the lives of American citizens. It was created by the Whig Party and a group of leading politicians like Henry Clay, John Quincy Adams, and Josh C. Calhoun.