Debussy's moonlight, provided that your university is not a conservatory of music. If it's a music school, play a dazzling tune. At least one of Liszt's "The Clock" will enter the charts. If you go to a general comprehensive university, don't try to show off your skills. Few people can understand it, but let's listen and everyone can understand it. Debussy's Moonlight is quite good, and the technical difficulty is at level 9. In this case, people who don't understand will feel good, and people who know will know that your level is relatively high.

You said that the first person in junior high school played fantasy improvisation, and the key to winning was that many people had heard that song. Technically speaking, the first movement of pathos is similar to fantasy improvisation, but it is not popular! A few people who don't study music have heard of Pathetique. I remember listening to a concert before, and I was sad. The performer had to rest after the last note when he played the Zhuangban at the end of the first part. Many people thought it was over and stood up and applauded. There was a board in the back, and someone stood up and applauded, which embarrassed the performers. So for people who don't understand, you think you are showing off your skills, and others may think it's ugly!