Final answer:
Some valid defenses to a defamation claim include truth, opinion, and privilege.
Step-by-step explanation:
Defamation is a legal claim that arises when someone's reputation is harmed by false statements published as facts. However, there are some valid defenses that can be used to counter a defamation claim. One defense is the truth defense, which means that if the statement made is true, it cannot be considered defamation. Another defense is opinion, as statements of opinion are protected under the First Amendment. Privilege is also a valid defense, which includes statements made in certain contexts such as court proceedings or legislative sessions.