The sixth subject: what it does and how to pick it
It is a safety net and a chance to learn something you like. It is not a percentage booster.
What CBSE says
Five main subjects are compulsory. A sixth, additional subject is optional. If you fail an academic elective and pass a sixth skill subject, the skill subject can replace the failed one in the result.
What it does not do
It does not automatically raise your percentage. Colleges that compute best of five may drop it if it is your lowest, which is the only sense in which it can help. Most admissions now depend on CUET, JEE or NEET rather than board percentage.
How to pick it
Choose for interest or a specific skill: Artificial Intelligence, Design, Mass Media Studies, Physical Education or a language. Avoid picking a sixth subject only because it is "easy"; every subject adds exams and practicals to your year.
Guidance based on the CBSE scheme of studies and public exam bulletins. Confirm rules with your school and the official sources before deciding.