Why is there an 'inflation' of top students in block C?

According to the 2024 high school graduation exam score data provided by the Ministry of Education and Training, none of the 5 traditional groups (also known as exam groups) had a perfect score (30 points/3 subjects). The highest score was for group C, 29.75 points; group D had the lowest, 28.75 points. Groups A and A1 both had 29.6 points; group B had 29.55 points.

The top scores of traditional exam groups this year and last year

Notably, block C has 19 valedictorians, the exam scores of the candidates are identical: literature 9.75; history and geography both 10. Of which, 13 valedictorians are from Bac Ninh; 2 are from Nghe An; the remaining 4 are from Ninh Binh, Nam Dinh, Thai Binh, Thanh Hoa.

The remaining blocks each have only one valedictorian. The valedictorian of block A is in Bac Ninh (math 9.6, physics, chemistry both 10). The valedictorian of block A1 is in Ho Chi Minh City (math and English both 9.8; physics 10). The valedictorian of block B1 is in Hai Phong (math 9.8; chemistry 10; biology 9.75). The valedictorian of block D is in Vinh Phuc (math 9; literature 9.75; English 10).

Compare the 10 points of the subjects physics, chemistry, biology, history, geography, foreign languages

To explain why there is an "inflation" of top students in block C, Thanh Nien Newspaper has made preliminary statistics of the 10 points of the exam subjects and found that there are some advantages for block C as follows:

Candidates taking history and geography exams outperformed those taking physics, chemistry and biology exams.

The 10 points "blossom" in history and geography, while they are quite "poor" in physics, chemistry and biology. Specifically, the number of 10 points in each subject is as follows: physics 53; chemistry 1,221; biology 34; history 2,018; geography 3,061.

The whole country has no candidate who scored 10 points in math in the 2024 high school graduation exam.

There were no 10s in math, the highest score was 9.8 and only 43 students achieved this level. In literature, 2 students achieved 10s (Dong Thap, Nam Dinh), 1,843 students achieved 9.75 points. Meanwhile, the number of candidates taking the math exam was slightly higher than the number of candidates taking the math exam, 972,753; and literature, 910,723.

Source: https://thanhnien.vn/diem-thi-5-to-hop-truyen-thong-vi-sao-lam-phat-thu-khoa-khoi-c-185240717153803602.htm