B.A Scope

You should opt for MBA in finance as you belong to finance background.

You may apply for MA or MBA program.

If you want to pursue your Masters in the field of economics, you can apply for MA (economics). This course is offered by a lot of colleges in India :
DSE Delhi, IMS Noida, Chaudhary Charan Singh University Meerut, Institute of Home Economics New Delhi & University of Petroleum and Energy Studies (UPES) Dehradun.
Among these UPES & DSE are top ones and in UPES, you can study specialised MA Economics course. It provides specialisation in Energy Economics.

The scope is limited as Assamese is only limited to the educational sphere of Assam. However, you have a lot of scope for Professorship in Assam, if you go for Masters along with Doctorate or B.Ed.

Graduation is a must if you seek a position in a good institution. It pays you more. Although, with time it's value has decreased. Now, even a Master's degree doesn't qualify you for a well paying job. You'll need Doctorates and various other qualifications. However, B.A. is the grassroot level of all. And it is definitely advisable to go for it.

What are your subjects and specialization?

Hello Zafar,
Career options after BA graduation are:
Higher Education / Studies :
B.Ed
MBA
MCA
MA
LLB
Diploma Courses
Short term Computer Courses
Hotel Management Courses
Fashion Design Courses

Sear Sachin Sharma,
You can go for taxation and then HRM, if you have done B.Com.
All the best.

Yes, you can go for UPSC exams and many other government jobs as well.