An important development or discovery in science and medicine due to industrialization was

During the industrial era, Louis Pasteur’s work helped establish germ theory: microorganisms, including bacteria, can cause and spread disease. That makes “Pasteur’s discovery that disease is spread by bacteria” the best answer. The other choices attribute discoveries incorrectly or refer to later developments, such as Salk’s polio vaccine.

AI-written and checked against the verified answer.