Which case exemplified the application of the First Amendment regarding political expression?

The correct choice illustrates how the First Amendment protects political speech and expressions, particularly in the context of campaign financing. Citizens United v. Federal Elections Commission is a landmark Supreme Court case from 2010 that ruled that corporations and unions could spend unlimited amounts of money on political advocacy, as long as the spending was independent of political candidates. This ruling emphasized that political speech, including spending for political purposes, is a fundamental right guaranteed under the First Amendment.

This case highlighted the Court's interpretation of free speech to include financial expenditures intended to influence elections. It underscored the principle that the government cannot restrict political speech based on the speaker's identity – whether that speaker is an individual, corporation, or union – thus reinforcing the idea that robust political expression is vital to democracy.

In contrast, the other cases primarily addressed issues like racial segregation or student rights, which, while significant, do not center on the specific application of the First Amendment to political expression in the same manner as Citizens United v. Federal Elections Commission.