As a UPSC aspirant should I take Btech CS or BBA LLB as my UG Degree? What may be the pros & cons of these degrees and which might give me an edge in prep as subject and time for prep is concerned? And which might be a safer backup even if i didn't crack UPSC or any such related exams

If you wish to go for UPSC, then whatever the degree you do doesn't matter. Your selection is entirely based on the preparation of UPSC CSE. You may choose any of the course as per your interest. My opinion will be that if you wish to go for the UPSC, and its your only goal, then don't go for the Integrated course. BBA LLB course is a good course, for those who want to make law a career. But you want to do UPSC CSE, and for that the law/rules/regulation will be provided you in the training schools. So being a LLB will not give you wings, compared to others who haven't done LLB. Its a 5 year course and I don't think it would be at all good for you to waste 5 years of your life in a course, which you won't get a career in. Instead, do a 3 years graduation and if required invest 2 years for attempts/better preparation.

If you wish to go for any of the two courses, my suggestion will be for you to go for the BTech CSE course. If you aren't confused, about what you want to do, then go for any of the courses and just keep on preparing for the UPSC CSE.

For more information regarding BTech CSE consider the link below:

https://www.careers360.com/courses/b-tech-in-computer-science-and-engineering

For more information regarding BBA LLB consider the link below:

https://www.careers360.com/courses/bba-llb-dual-degree

For more information regarding UPSC CSE preparation tips consider the link provided below:

https://competition.careers360.com/articles/how-prepare-for-upsc-ias

I hope this helps. Wish you a great day!