Yes you can give the UPSC IAS exam without leaving NDA. Since you've gotten into NDA, you must be a hard working candidate and you will not get much difficulties while preparing for the exam.
Also, yes you can leave NDA if you're selected in the IAS exam.
Good luck!!
Answer Key | Eligibility | Application | Admit Card | Preparation Tips | Result | Cutoff
Application | Eligibility | Answer Key | Result | Cutoff | Selection Process | Preparation Tips
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