Hello aspirant,
You have not made any mistake in your KCET application form. Even though you are not appearing for Biology exam in KCET you will get names of all the subjects in your admit card. But it is not compulsory for you to write Biology paper. If you are aiming for Engineering courses and have opted only for Physics, Chemistry and Mathematics t hen you have to write the exam for only these papers.
So, do not worry, you'll only have to write the exams for thjose papers which you have opted. It is not compulsory to write Biology exam.
Further, to know more information about the KCET Exam form, application form, etc - you cna follow the below mentioned link to know more on this : https://www.careers360.com/exams/kcet
I hope that this will help.
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