Hii dear, 

As you are in  final year of your course ,so  you are absolutely eligible to appear for the CDS Exam.

This is because the required educational qualifications for the CDS Exam is :

Either the candidate should have completed graduation from any recognized college/university or candidates in final year of graduation can also apply for the same.

There is no percentage bar applicable for this exam.

Hope this helped. 

Good luck!