Precedent in Tinker v. Des Moines is shown through citations of previous cases like Cox v. Louisiana and Adderley v. Florida to support the argument about protecting 'pure speech' under the First Amendment.
Precedent in legal terms refers to past decisions that can influence current cases. In the context of Tinker v. Des Moines, the excerpt that shows how precedent supports an argument is option C. This excerpt references previous cases like Cox v. Louisiana and Adderley v. Florida to support the argument about the protection of 'pure speech' under the First Amendment.
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