\Read this passage.
In March 1953, Dr. Jonas Salk announced that he invented a vaccine that prevented polio. Polio attacks the nervous system and can cause paralysis and death.
Which sentence could be added to the passage and maintain its formal style?
Pretty soon, with the use of the vaccine, nobody got sick with polio.
Pretty soon, with the use of the vaccine, nobody got sick with polio.
The discovery of the vaccine helped save the lives of many people, including mostly children.
The discovery of the vaccine helped save the lives of many people, including mostly children.
Before the vaccine, most people had to be put in an awful “iron lung” to help them breath.
Before the vaccine, most people had to be put in an awful “iron lung” to help them breath.
Without the vaccine, polio cases were everywhere because it could spread super easily.
the last question is answer:
Without the vaccine, polio cases were everywhere because it could spread super easily.