Hii Tarun, 

Biomedical is the study of humans, whereas biological science is the study of animals and plants and life science deals with the living organisms. So now it's choice of your own interest. Any subject taken with interest would fetch you with better results. All the very best! 

• Biomedical sciences are a set of applied sciences applying portions of natural science or formal science, or both, to knowledge, interventions, or technology that are of use in healthcare or public health. 

• Biological Sciences aims to educate students about developing new bioinformatics tools. They also learn about Biomaterials, Biomechanics and Cell and Tissue Engineering, Biomedical Devices, Computational Bioengineering, Biomedical Imaging, Premed and Synthetic Biology. Students acquire knowledge about applying engineering principles to the re-conceptualisation of biological phenomena. Training is imparted to them to develop new materials and processes, which would include genetic modification of agriculturally important plants and human cells.

• Life science deal with thescientificstudy of all the differentlifeforms i.e. thescientificstudy of living organs like plants, animals and human beings. B.Sc. (Life Sciences) degreecourseinvolves study of the various processes oflifee.g. the process involved for the change from molecular to cellularlife.