If the code of the enrollment brochure you see has changed, for example, to 303, it means that they have decided to take the third math exam, and this change is possible. You can refer to the previous admissions brochure. This year's enrollment brochure hasn't come out yet. If you read it on the website you want to apply for, it may indeed change.
If the admissions brochure is the same as before, you may have bought the wrong test paper. You can have a look at Li Yongle's complete answer to the real question upstairs. This is a good book.
30 1 Math I 302 Math II 303 Math III 304 Math IV