Salk vaccine is a:
c. Killed vaccine(Ref: IAP Guidebook on Immunization 2013-14; pg 113-117, Nelson's 20/e p 3212, Ghai, 8/e p 190- 191)Polio vaccines were developed in the USA during 1950, first the inactivated polio vaccine (IPV) by Jonas Salk and later the live oral polio vaccine (OPV) by Albert Sabin. Remember: 'Salk' is a 'killed' vaccine.
Live vaccine
Live attenuated vaccine
Killed vaccine
Toxoid
Immunization