Which of the following sanctions is NOT within FIFA's powers against a football agent who has breached regulations?

Incarceration for short periods of time for any serious offenses is not within FIFA's powers as a sanction against a football agent. FIFA, as the governing body of soccer, has the authority to impose administrative sanctions related to the sport, such as fines or the suspension of licenses. These actions are designed to maintain the integrity of the game and ensure compliance with regulations.

However, incarceration is a legal matter that falls under the jurisdiction of criminal law, which is outside FIFA's purview. FIFA cannot impose prison sentences or enforce criminal penalties, as these actions require the involvement of law enforcement and the judicial system. Thus, while FIFA can take measures to regulate and discipline agents within the context of the sport, it does not have the authority to impose incarceration.