B.A

If you have will, dedication and readiness to put extra efforts to prepare for Civil Services along with your graduation studies, then you must go ahead.
All the best.

Yes, but you've to search for the institutes which offers the concern subjects.

B.A. (Hons) in Psychology is said to have more scope as it is not subject-specific and it contains a lot of important parts. In comparison, Applied Psychology is subject-specific and limited.
Hope I helped. Thanks.

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.

Hello,
You can opt for your Honors subject or you can select a discipline that is closely linked to your Honors subject, as it will improve your job opportunities.

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.