UPSC doesn't restrict to give your examination in your own language.  Gujarati language is an integral part of 8th schedule. Thus you can opt for Gujarati while writing the General studies paper provided you have to attempt the English language as a separate paper. Also you can't opt Gujrati in prelims, it is only applicable for Mains and Interview only.

To know more about UPSC visit the link below:

https://competition.careers360.com/exams/upsc-civil-services-exam

I hope this answer helps. All the very best for your future endeavors!

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