When you are divided into majors, you will generally choose this category of majors. However, as long as your grades are good enough and your GPA is high enough, it is ok to choose a major across major categories, which means you can choose from the whole school. Professional details can be found on the undergraduate enrollment network of Zhejiang University. Generally speaking:

Science: Mathematics and applied mathematics (including operations research), information and computing science (including information processing and information security, computer graphics), statistics (including financial mathematics, actuarial science and biological mathematics), physics (including electronic information), chemistry, applied chemistry (including chemical biology), geographic information science and technology, geographic information system, resources, environment, urban and rural planning and management, and atmospheric science.