Which of these acts is protected under the First Amendment?

The First Amendment of the United States Constitution protects several fundamental rights, including the freedom of speech, which encompasses the right to express opinions about the government and its officials. Criticizing elected leaders is a vital aspect of a democratic society, allowing citizens to engage in discourse about their government and hold leaders accountable. This form of speech is protected even if it is offensive or critical, emphasizing the importance of free expression in a healthy democracy.

The other options, while related to speech, involve actions that are not protected by the First Amendment. Selling pornography to children is illegal due to the protection of minors from harmful material. Telling military secrets to the enemy compromises national security and may fall under laws concerning espionage. Spreading untrue rumors can be deemed defamatory, which is not protected under the First Amendment, as it can cause real harm to individuals' reputations. Therefore, the act of criticizing elected leaders stands as the clear example of an action that is explicitly protected under the First Amendment.