It depends on the interest and career goals. All fields have merits and drawbacks.

M.Sc. in Zoology:

Area of Emphasis: It is concerned with the study of animals along with their behavior, ecology, and evolution.

Career Scope: Research institutions, organizations for wildlife conservation, zoos, and academic institutions.

Best Colleges: Delhi University, Banaras Hindu University, University of Hyderabad.

M.Sc. in Biotechnology:

Focus: This program is all about the exploitation of biological processes to formulate new products and technology.

Career Opportunities: Biotechnology industries, pharmaceutical companies, research organizations, and academic institutions.

Best Colleges: IITs, IISc Bangalore, JNU, University of Delhi.

M.Sc. in Microbiology:

Focus: This program is focused on the study of microorganisms and their interactions with other organisms and the environment.

Career Options: Pharmaceutical companies, research institutions, food industries, and healthcare sectors.

Best Colleges: Delhi University, BHU, JNU, IISc Bangalore.

Key things to keep in mind while selecting a course:

Interests: Choose a program that you feel would be of interest to you and related to your passions.

Career Goals: Consider your long-term career goals and choose a program which could serve that purpose.

Reputation of College/ Faculty: Every institution has its reputation and you must assess this to make your choice of a program.

Infrastructure and Facilities: Infrastructure and research facilities are the required needs of quality education.

Placement Opportunities: The college placement record and industry exposure will help you to make the right choice of the college.

So at the end, it depends upon your preference and what you really want to achieve. Before making a choice, research work on the different colleges, faculty, curriculum, and the respective placements.