The correct analysis of the effect of the Supreme Court’s use of selective incorporation on the freedom of expression is:
Selective incorporation has expanded the freedom of expression by forcing states to protect the freedom of speech.
Selective incorporation refers to the process by which the Supreme Court has applied certain provisions of the Bill of Rights to the states through the Fourteenth Amendment's Due Process Clause. This has effectively ensured that states cannot infringe upon rights like freedom of speech, thereby expanding the protections afforded to individuals regarding expression.