The correct option is D Small pox
Smallpox is an acute contagious disease caused by the variola virus, a member of the Orthopoxvirus family. It is completely eradicated from India in 1977 when A WHO International Commission comprising experts in epidemiology and infectious diseases from 16 countries carefully reviewed the data. They made field visits to states, district- and health centre levels, as well as to villages to assess on the spot the validity of information. After reconvening in Delhi, they concluded that smallpox had been eradicated from India by proper vaccination in the population. Polio has still not been eradicated from India but polio-free status has been maintained in India from last 3 years. Hence option D is correct.