B.Sc Scope

You should opt for physics.

Hi,
You know both physics and marine are differ from each other. This is better for you that you can continue the same subject in M.Sc as well. Yes, after completing the B.Sc in physics, you can pursue Masters in marine geo physics, if you want.

As mentioned in the above answer you can pursue M.Sc. You are already in the same stream.

Hello Riyanka,
Following are the higher studies options after B.Sc. in statistics:
M.Sc. in Actuarial Science
M.Sc. in Library and Information Science
M.Sc. in Quantitative Economics
MCA
Masters in Math
Masters in Statistics
MBA
P.G. Diploma in Stat. Methods with Applications
Specialist Development Program in SQC
JRF & SRF Rules
Junior/Senior Research Fellowship

You can opt for an M.Sc in any field of biological science. Then may be go for research and Ph.D. You can also look for jobs in the biological sector.

MBA and M.Sc are two different streams. MBA belongs to the management field, and M.Sc belongs to the technical field. If you want to be in technical space, opt for M.Sc and not MBA, and vice versa.

If you are in Maharashtra, you should apply for municipal jobs, which have vacancies under the Maharashtra Government as there are many public-private health institutions opening up in Maharashtra, which requires phlebotomists who are qualified and trained in their work.