Explanation:

- Option 2: Jonas Salk

- Jonas Salk was the inventor of the first successful polio vaccine, developed in the 1950s.

- His inactivated polio vaccine (IPV) has significantly reduced polio worldwide.

- Salk's work was crucial in preventing the devastating impacts of polio.

- Option 1: Ernest Haeckel

- Haeckel was a German biologist and philosopher.

- Known for his work in evolution and the theory of recapitulation.

- Not related to the development of the polio vaccine.

- Option 3: Linus Pauling

- Pauling was a renowned chemist and peace activist.

- Known for his work in chemistry and advocacy for vitamin C.

- Not associated with the polio vaccine.

- Option 4: Robert Wellberg

- There is no record of a significant scientific contribution from someone named Robert Wellberg related to the polio vaccine.

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