It totally depends on which type of career you want to do in future. 

If you want to practice law by your own then B.Com LLB is best by doing this course you will be specialise in the various fields like accounting and taxation. 

If you want to work in business field then BBA LLb has more scope. You can apply in various managerial position in a company like the corporate legal adviser, mergers and acquisitions.

At Last, it totally depends on your interest if you have interest in management go for BBA LLB and if you want to do work as a legal advisor you can go for B.Com LLB.

Good Luck!!