One of the reasons for the success of the smallpox eradication campaign was that a. smallpox viruses were used in the vaccine. b. smallpox was not a transmissible disease. c. smallpox occurred only in humans. d. smallpox occurred only in south america. e. smallpox could be treated with antibiotics.

One of the reasons for the success of the smallpox eradication campaign was that small pox only occurred in humans. Smallpox is an extremely contagious and deadly virus for which there is no known cure. it is caused by two variants, Variola major and Variola minor. it is a disease of the past that was eliminated by worldwide vaccination. 

If you want the answer you need to post the figure above that it's talking about and you

If you remove all the lions from the savanna it will lead to a increase of gazelle and a increase of cheetahs becasue of no competition