All questions in Stream-SA are compulsory (Science and Mathematics) With respect to Stream SB and SX, there will be four sections in Part I (Physics, Chemistry, Biology, and Mathematics) and four sections in Part II (Physics). Chemistry, biology, and mathematics).  Candidates can answer any of the four subjects in Part I and any two of the four subjects in Part II. If the candidate attempts more classes, three best in Part I and two best in Part II are considered.