if i select bsc (zoology, botany, chem.) then what career options i cn pursue?

This a great career interest for people who are fascinated with nature and would not mind spending time understanding it. There are several specializations that the students pursuing the field can venture into. There are physiologists that study the metabolic processes of animals, then there are taxonomists who deal with the naming and the classification of the animal species, one can think of becoming embryologist whose only job is to study and focus on the early stages of the animal life. So similarly there are many such options that one can venture into depending on his / her capabilities and interests. On choosing this career, the person specializing in the field will be referred to as a zoologist. On being a part of this field, one will be carefully have to study the behavior, characteristics, evolutionary trends of the different species of animals and those factors having a direct impact on them.

A zoologist might even get to travel because the nature of his / her job. Channels like National Geographic, Animal Planet, Discovery Channel are in constant need of Zoologists for research and documentaries. Zoologists are also hired for zoos, wildlife services, botanical gardens, conservation organizations, national parks, nature reserves, universities, laboratories, aquariums, animal clinics, fisheries and aquaculture, museums, research, pharmaceutical Companies, veterinary hospitals, etc.

In Botany:

You can join Botanical Survey of India (BSI),National Institute of Oceanography (NIO),Indian Agricultural Research Institute (IARI),Indian Council of Forestry Research and Education (ICFRE) etc. as Project Assistant, Technical Assistant, Field Assistant or Scientific Assistant. Relatively there are less opportunities available for them in private sector when compared to public sector. It is possible for them to work in private firms like Nursery Farms, Environmental Consultancies etc. as Environmental Consultant, Nursery Manger or Greenhouse Manager.

Hope this helps.

Good Luck.