Considering how it has been used, which of the following sentences about the Incorporation Doctrine is true?

(1 point)
• It only applies to the First Amendment.
• It protects the federal government from the power of citizens.
• States must agree to be ruled by the Incorporation Doctrine.
• The Incorporation Doctrine applies to cities and school districts.

The sentence about the Incorporation Doctrine which is true is: The Incorporation Doctrine applies to cities and school districts.