The correct answer is 1 and 3 only.Covaxin:?It is an inactivated pathogen-based vaccine.It is developed with Whole-Virion Inactivated Vero Cell-derived technology.They contain inactivated viruses, which can not infect a person but still can teach the immune system to prepare a defence mechanism against the active virus.Covishield:It ?is a recombinant, replication-deficient chimpanzee adenovirus vector vaccine.It has been modified to enable it to carry the COVID-19 spike protein into the cells of humans. Hence, statement 2 is incorrect.Sputnik V:It is a viral vector vaccine designed to produce lasting immunity against COVID-19.It is based on adenovirus DNA.Adenovirus is used as a carrier to deliver the coronavirus gene to cells and synthesize the SARS-CoV-2 virus's envelope proteins, introducing the immune system to a potential enemy.The cells then use the gene to produce the spike protein. A person's immune system will treat this spike protein as foreign and produce natural defences, antibodies, and T cells, against this protein.