The Tenth Question: All or Nothing!

is episode 25 of the original Naruto anime.

Synopsis
Forty-five minutes into the written portion of the Chūnin Exams, Ibiki announces that it is time for the tenth and final question. But he ominously states that there is one special rule for this question. Meanwhile Kakashi Hatake, Asuma Sarutobi and Kurenai Yuhi rest at the Academy staff room and discuss their respective teams' chances of passing the first phase. Kakashi and Asuma explain to Kurenai that Ibiki specialises in interrogation and knows how to get inside the minds of his victims

Back at the exam, Ibiki states that the candidates are free to choose whether or not they want to try and solve the tenth question. If they opt out, the entire team will fail. If they choose to answer the question but get it wrong, they will be barred from taking the Chūnin Exams forever. Several teams decide to leave rather than risk it. Naruto doesn't have any answers to the first nine questions and knows that the odds of him knowing the answer to the tenth are exceedingly small. He seems to waver but finally exclaims in his loud style that he will not be intimidated and will become Hokage even if he fails and remains a genin forever. This outburst calms the remaining teams, and everyone is determined to stay for the remaining question. Seeing that no one else is going to leave, Ibiki passes them all. He explains that the first nine questions were to test their information gathering skills, whereas the tenth was to test their determination and bravery.

The first phase of the exam completed, Anko Mitarashi spectacularly crashes through the window and states she is the second examiner. After the students leave, Ibiki picks up Naruto's exam paper and smiles to himself, realising he just passed a student who didn't answer a single question. The next day the candidates gather outside the Forest of Death.