Option 1: Alexander Fleming is not the correct answer. While Fleming made significant contributions in the field of medicine, particularly with the discovery of penicillin, he did not disprove the theory of spontaneous generation.

Option 2: Joseph Lister also did not disprove the theory of spontaneous generation. Lister is known for introducing antiseptic techniques in surgery to prevent infection, but his work did not directly address the theory of spontaneous generation.

Option 3: Louis Pasteur is the correct answer. Pasteur performed experiments in the mid-19th century that disproved the theory of spontaneous generation. His experiments involved boiling broth in curved neck flasks, which allowed air to enter while preventing the entry of microorganisms. The broth remained free from microbial growth, demonstrating that life does not spontaneously generate but instead comes from preexisting life forms. This experiment provided evidence for the principle of "life begets life" and laid the foundation for the field of microbiology.

Option 4: Linus Puling is not the correct answer. Although Linus Pauling was a renowned chemist and made significant contributions to our understanding of chemical bonding and protein structure, he did not disprove the theory of spontaneous generation.