Is it possible to improve my 12th marks by taking an exam to apply to better universities in UK/Singapore?

Yes, you can improve your 12th-grade marks by retaking exams, which can help with university applications - especially in the UK.

- UK: Most universities accept A-Level resits, and your improved grades will be considered for admission. However, some universities may have specific policies about resits, and too many attempts might be viewed less favorably. - Singapore: Universities typically do not allow students to retake exams just to improve grades. Retakes are generally permitted only for valid reasons like illness.

Make sure your updated results are available before application deadlines.