In a class, there are three types of students: A, B, and C. Type A students are good at mathematics, Type B students are good at science, and Type C students are good at literature. If John is a Type A student and Sarah is a Type B student, which of the following statements is true?
Four friends, A, B, C, and D, attended a seminar on different days. A attended before B but after C. D attended on the last day. What is the correct sequence of attendance?