The marking scheme for the preliminary examination in the UPSC consists of two papers, each worth 200 marks. Candidates must attempt both General Studies papers, with a negative marking of 1/3 for incorrect answers. The total score is calculated based on the marks obtained in both papers. To qualify for the Mains examination, candidates need to secure a minimum cutoff score, which varies each year. Marks from the preliminary segment are not carried forward to the subsequent stages of the examination process. Thus, individual performance in the preliminary exam is crucial for advancement.