Of all the AP Tests administered during the May 2023 session, the Chinese Language one had the highest average score, with 4.09 among 16,495 students.

2021: https://reports.collegeboard.org/media/pdf/2021-ap-student-score-distributions_1.pdf
2022: https://apcentral.collegeboard.org/media/pdf/ap-score-distributions-by-subject-2022.pdf
2023: https://apcentral.collegeboard.org/media/pdf/ap-score-distributions-by-subject-2023.pdf