In What Way Was Dr

In what way was Dr. Semmelweis's finding about preventing childbed fever generalized to other areas?

A) Midwives are better at assisting women give birth than doctors are.
B) Letting medical students treat patients with doctors leads to an increase in disease incidence.
C) All hospitals of the day improved their ventilation systems.
D) it has turned out that lack of sterilization can cause many diseases
E) When people get frustrated trying to solve medical mysteries, they now routinely go on vacation.