50. Course requirements in university systems_________in different countries around the world. In most of the European universities, students are not required to attend classes. However, students in the United States are required to attend all classes and may be penalized if they do not. Besides, in the European system, students usually have to take one comprehensive examination at the end of the entire four or five years of study. But, there are usually numerous quizzes, assignments, or final papers in each course at the end of the semester in the university systems in the United States.(A) should be reformed drastically(B) will be transformed steadily(C) may reshape education comprehensively(D) can differ considerably