Answer:
Discovery of vaccine for smallpox, viruses and actual organisms that cause many diseases lead to the development of Germ Theory.
Explanation:
- Theory was the 'predominant theory' of 'disease transmission' before germ theory but it is no longer accepted as a 'scientific theory' of diseases.
- 'Formal and reliable experiments' on germs and diseases relationship were 'conducted by Louis Pasteur'.
- He showed that growth of microorganisms was not a spontaneous generation and his pasteurization experiment provided key pieces of evidence that supported germ theory.