Which field will be beneficial in MBA?

Yes, MBA can help you sharpen your skills in Business Management, and thus assist you in the professional career. However, keeping your interest areas in mind, you need to decide what specialization you need to do from a career perspective. The chances of doing well in a career of one's interest are

Good evening, For a B.Com student, MBA in Finance would be a better option. But if the candidate has interest in other fields like marketing or operations than that would also be good. As Finance is the basic subject which is taught B.Com. So pursuing MBA in Finance and Operations would be better.