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When students are 16 years old they may take an exam in various subjects in order to have a qualification. These qualifications can be either G. С. S. E. (General Certificate of Secondary Education) or «0 level» (Ordinary level). After that students can either leave school and start working or continue their studies in the same school as before. If they continue, when they are 18, they have to take further examinations which are necessary for getting into university or college.
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Why do the students have to take further exams after G. C. S. E. or «0 level»?
They are necessary for continuing studies at school.
They are necessary for starting to work.
They are necessary for personal purpose.
They are necessary for entering a university or a college.