Best option to do PhD is to go for bsc in any stream of your choice in biology then do your MSC and then PhD



Good luck !!!

Dear



As per your query and According to me you can consider these options in bachelor



Life sciences

Zoology Hons or Biotechnology



Then after 3 years then you have options in master like



Microbiology

Stem cell

Nanotechnology

Genetic science



When you are in master then you can take guidance from the Faculties to choose the research topic in PhD .



All the best

First bsc, then msc, then PhD.. It's a pretty good career option now a days..