The Chunin Exam arc in Naruto showed the rest of Naruto's class in action after Team 7's time in the Land of Waves. Plot-wise, it was the next step in Naruto's path to becoming the Hokage, but in reality, it was to highlight the unique fighting abilities that the other genin had up their sleeves. The first two phases of the exam were team-based, but phase three devolved into one-on-one combats.
Source：https://www.cbr.com/naruto-chunin-exam-fight-winner/
