B.A Scope

Yes, you can do MA after completing BA. You only need Bachelor's degree in arts stream for taking admission in MA Sanskrit.
Academic options:
Upon successful completion of the course, postgraduates interested in further studies in the discipline may go for pursuing MA in Sanskrit literature, B.Ed or PhD in Sanskrit or Masters in mass communication and journalism with specialisation in Sanskrit Patrakarita.Other options include pursuing Postgraduate Diploma in Functional Sanskrit and Translation, or Post-Graduate Diploma in Sanskrit Journalism. Rashtriya Sanskrit Sansthan also offers such postgraduates the option of taking vocational training in Sanskrit short-hand and typing and cataloguing manuscripts.

Scope for BA Statistics course:
This career offers great job opportunities in India and also abroad. The statisticians and their analytic skills are highly demanded in today's job market. You can use statistics in various fields such as business, industry, agriculture, government, private, computer Science, scientific, health sciences & other disciplines. After completing you study in statistics, you can also apply for the Civil Services, Indian Statistical Services & Indian Economic Services exams. Those complete the degree, one can opt for finance, analytics, software development, actuarial Science & many more options. Top institutes which offer B.A. In statistics are mentioned below:
1) Indian Statistical Institute (ISI), Kolkata
2) ST. Stephen's College
3) ST. Xavier's College, Mumbai
4) ST. Xavier's College, Kolkata
5) Hansraj College
6) Hindu College
7) Lady Shri Ram College for Women
8) Ramjas College
9) Kirori Mal College
10) Indian Institute of Technology, BHU, Varanasi
Regards.

Hi Ritirupa,
Mass Comm. & Journalism would open up lot of opportunities for you, provided you have interest in them. There is the obvious one, entering journalism in any print or electronic media. It does't always have to be as a reporter or anchor, but can be any other back end or front end jobs in media. Then there is advertising, Public Relations, Film-making, Photography, Cinematography, content writer an so on. The possibilities are endless as communication is the base of everything. You will have to make up your mind as to which way you want to go. Coming to the second part of your question, completing your graduation in Mass Comm and Journalism might not be of any extra assistance in bank exams. You do have to be graduate to apply for bank jobs, so yes you will be eligible for selection, that is after you clear the bank exam.
Hope this helps!

ELIGIBILITY CRITERIA for MCA
Since this is a PG course, Bachelors Degree is required to be considered eligible to pursue MCA course. Any graduation Degree will do, provided that the student has 10+2 Science stream schooling with Physics, Chemistry and Mathematics subjects under his/her belt. Usually, it would be better to pursue MCA after going through a relevant Bachelors Degree programme that is related to Computers, Networks, Programming and Web Technology.
Regarding the 10+2 Science stream schooling requirement, some exceptions exists. For example, B.Com. Computer Science and B.Com. IT Graduates (who had Commerce stream schooling in 12th standard) may also pursue MCA programme!

After BA In political Science, as a student of political Science you can pursue your career in the various field, or else there are several exams for which you can apply with the Government of India. You can apply for the exams conducted by the UPSC SSC State level PSC, IBPS Bank PO and Clerical exams, other Bank PO and clerical exams etc.
You can even try to get jobs with the private sector organization. If you are planning to get a job based on political Science, then the scope is wide and you can choose from a wide range of job profile like, Activist, Administration in Corporate or Government or Non-Profit organization, Online Political Data Analyst, Budget Examiner or Analyst, Public Affairs Research Analyst, Public Opinion Analyst, Research Analyst, State Legislator, Survey Analyst, Systems Analyst, University Administrator, University Professor, Banking Analyst or Executive, Campaign Operative, Career Counselor, Editor, Online Political Journal, Federal Government Analyst, Free-lance writer, High School Government Teacher, Journalist, Policy Analyst, Political Commentator etc.