Textbooks for senior one and senior two are compulsory, regardless of arts and sciences. Students can take the college entrance examination and the national examination. Students in the second volume can choose to study A or B (in fact, it is decided by the school or the local education department). The difference between A and B is that A uses traditional geometric methods to solve solid geometry problems, while B pays more attention to the application of space vectors in solving solid geometry problems besides traditional geometric methods. The college entrance examination does not test space vectors separately. There are two answers to the college entrance examination solid geometry questions, namely, space vector method and traditional geometry method. Space vector method is usually easier to learn. Some schools stipulate liberal arts version A and science version B, which is their own stipulation, not the original intention of the textbook writers. You can choose both a and b versions of arts and sciences, but b is simpler and you can naturally master the method of a, and vice versa.