M.Sc

Nutrition Science is also an allied subject of Life Sciences or Biological Sciences or Home Sciences. Therefore as you are graduated from Life Sciences or having a B.Sc Degree in Life Sciences subject then you are definitely eligible for pursuing Masters or M.Sc in Nutrition or allied fields from any recognized institutes or universities from India or even abroad. Best of luck.

I request you to share your education background first to know which course is actually relevant to you. Although all these three courses are professional and have their own importance. But for instant job perspectives Agribusiness management could be a better option.

Gisma Business school is a good institution in Germany. They hold the #31 rank in Germany and #657 rank worldwide as a management school. So, I think its a good option to choose.

GISMA Business School is a good institution in Germany. They hold the 31 rank in Germany and 657 rank worldwide as a management school. Its placement stats and faculty member's credential also support its worth to be chosen as an institute to learn and get admitted. And good news for you is that Germany is offering a lot of scholarships to Indian students which makes your decision even more worthy.

Pathology is also an allied subject of Life Sciences or Biological Sciences. Therefore, as you are graduated from Life Sciences or having a B.Sc Degree in Zoology subject, then you are definitely eligible for pursuing Masters or M.Sc in Pathology or allied fields from any recognised institutes or universities from India or even abroad. Best of luck.

Yes, you can do MS in UK after you finish your programme. And IELTS. So, the first thing for you to do right now is to concentrate on your degree. The last 2 years are especially important. Try to score above 70 percentage or equivalent. Then soon after you finish your UG there would be a small period of waiting for your degree certificate. If so. Get some work experience while you wait. Then once you get your degree certificate. Appear for IELTS. Then apply for any university you like in UK.

For M.Sc agriculture, you should appear in ICAR AIEEA.
ICAR AIEEA 2020 Exam Dates have been announced by NTA. The exam will be held on 1st June 2020 through online mode. It will be conducted to offer admission in UG & PG courses. Indian Council of Agricultural Research (ICAR) will organize the All India Entrance Examination for Admission (AIEEA).

Yes, you are eligible for Masters in Pathology.

https://www.shiksha.com/m-sc-master-of-science-chp
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Few universities have their separate entrance exam for Microbiology i.e. University of Mysore and it consists of following topics:
General Microbiology. The Microbial World. Microbial Growth and Metabolism. Microbial Genetics. Environmental Microbiology. Genetic engineering. Microorganisms in agriculture. Food Microbiology. Best of luck.