The written exam is the first stage of the NDA (National Defence Academy) selection process. It consists of two papers - Mathematics and General Ability Test (GAT). The marking scheme for the written exam is as follows:

Mathematics:
- This paper consists of 120 questions, each carrying 2.5 marks.
- For correct answers, candidates are awarded 2.5 marks.
- For incorrect answers, 1/3rd of the marks are deducted as negative marking.
- Unattempted questions do not carry any marks or negative marking.

General Ability Test (GAT):
- This paper consists of 150 questions, each carrying 4 marks.
- For correct answers, candidates are awarded 4 marks.
- For incorrect answers, 1/3rd of the marks are deducted as negative marking.
- Unattempted questions do not carry any marks or negative marking.



The SSB (Services Selection Board) interview is the second stage of the NDA selection process. It consists of a series of tests conducted over a period of 5-6 days. The marking scheme for the SSB interview is as follows:

Psychological Tests:
- These tests assess the candidate's personality, intelligence, and aptitude.
- The scoring is based on various factors such as leadership qualities, problem-solving skills, communication skills, etc.
- There is no specific marking scheme for these tests, as the assessors evaluate the overall performance and potential of the candidate.

Interview:
- The interview is conducted by a panel of experts who assess the candidate's suitability for a career in the armed forces.
- The interview panel evaluates the candidate's knowledge, communication skills, confidence, and attitude.
- There is no specific marking scheme for the interview, as the assessors make an overall assessment of the candidate's performance.

Group Testing Officers (GTO) Tasks:
- These tasks evaluate the candidate's ability to work in a group and demonstrate leadership qualities.
- The GTO tasks include group discussions, group planning exercises, outdoor group tasks, and individual obstacles.
- The assessors evaluate the candidate's participation, contribution, leadership, and problem-solving skills during these tasks.

Conference:
- The final assessment is done during the conference, where all the assessors sit together and discuss the performance of each candidate.
- The assessors make a collective decision based on the candidate's performance in all the tests and tasks conducted during the SSB interview.



The marking scheme for the written exam and the SSB interview in the NDA selection process is different. The written exam has a specific marking scheme with negative marking for incorrect answers, while the SSB interview assesses the candidate's overall performance and potential without a specific marking scheme. It is important for candidates to prepare thoroughly for both stages of the selection process to increase their chances of success.