Where does Yu Xixi go to college?

University of California, Santa Barbara.

Yu Xixi got good grades, because Yu Xixi studied at the University of California, Santa Barbara, which belongs to the University of California system and is the top research science in the United States.

The University of California, Santa Barbara is the top institution of higher learning in the world. Yu Xixi can study in this school, which shows that her grades are really good, otherwise she will not be admitted.