For the dance that is biased towards the national style, you can ask the teacher to make up a paragraph for you, which takes about 30 seconds to one minute, preferably no more than one minute. Because if it's an art test, the judges can't let you perform for long. To be short and pithy, you can make up some movements that are not difficult but look great.
Don't choose vocal music and musical instruments because you have no foundation. Of course, you can also choose hip-hop, because hip-hop is short and pithy. For the judges, it is a piece they seldom touch. People who don't know much about it will think it is very powerful, and the content of hip-hop will be very explosive in about 30 to 40 seconds.