What is the maximum number of years someone can serve as president?

The correct answer is based on the 22nd Amendment to the United States Constitution, which was ratified in 1951. This amendment limits an individual to serve as president for a maximum of two elected terms, which amounts to eight years. However, it also allows for the possibility of a president serving up to ten years if they were to inherit the presidency through succession. This situation can occur if a vice president takes over for a president who is unable to finish their term and then serves more than two years of that term. Consequently, if a vice president serves out the remainder of a term lasting less than two years and then is elected for two additional full terms, they could effectively serve a maximum of ten years in total.

Thus, the correct understanding of the maximum presidential tenure considers both elected and succession scenarios, leading to the conclusion that someone can potentially serve up to ten years.