Final answer:
The tribunes were elected officials charged with protecting the plebeians' interests, possessing veto power to stop any actions harmful to plebeians and having the ability to introduce legislation to the Plebeian Assembly.
Step-by-step explanation:
The tribunes were elected officials in ancient Rome whose main responsibility was to protect the interests of the plebeians, which was the common class of Roman citizens. Specifically, after 450 BCE, the Plebeian Assembly would annually elect ten tribunes. These tribunes had the power to attend meetings of various Roman governing bodies, such as the Senate and the law courts, and if they identified any action that could harm the plebeians, they could utilize their veto power to stop it by saying "Veto" or "I forbid." This power served as a check on the authority of patrician officials, ensuring the protection of plebeians' rights.
Further expanding on their role, the tribunes could also present laws to the Plebeian Assembly for approval, effectively allowing them to influence the legislative process in favor of the plebeians. Throughout the history of the Roman Republic, the influence of the tribunes and the rights of plebeians increased, with plebeians eventually being able to serve as consuls and senators, marking the conclusion of the Struggle of the Orders.