Hi,
Yes they can write IISER exam.
See the exam is divided into 4 parts and has 15 questions from Each Subject.
Physics - 15 Questions
Chemistry -15 Questions
Maths- 15 Questions
Biology - 15 Questions
No Sectional Cut Offs .
Most of the students who appear in the IISER Aptitude Test will have either PCM or PCB in Class 12 and only few will have PCMB as subject and they might have an edge over other students.
If you are a PCM Student - You can really do good in PCM Questions + Study NCERT Level Biology
The Syllabus is
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