Final answer:
The Supreme Court ruled in favor of the students in Tinker v. Des Moines, supporting their freedom of speech, as wearing armbands in protest did not materially interfere with school operations and was protected under the First Amendment.
Step-by-step explanation:
In the events surrounding Tinker v. Des Moines, the Supreme Court ruled that the wearing of armbands as a form of protest on public school grounds is protected by the First Amendment. This decision therefore supports C) the students' freedom of speech. The Court held that the armbands represented 'pure speech' that is entirely separate from the actions or conduct of those participating in it. Furthermore, it was established that students do not lose their First Amendment rights when they step onto school property. To justify suppression of speech, school officials must prove that the conduct would 'materially and substantially interfere' with school operations, which was not demonstrated in this case.