Pasteur's experiment provided conclusive evidence to reject the spontaneous generation hypothesis, which states that
cells arise from nonliving material. As a consequence, his results supported the all-cells-from-cells hypothesis. Which
element of Pasteur's experimental design was most important and why?
His two treatments differed only in the shape of the flask, resulting in exposure of only one of the treatments to preexisting cells.
His two treatments differed in the shape of the flask, the type of nutrient broth, and the amount of time the broth was boiled,
allowing him to test multiple factors.
His two treatments differed in both the type of nutrient broth and the shape of the flask, resulting in the exposure of only one of the
treatments to preexisting cells.
His two treatments differed only in the type of nutrient broth used, resulting in the exposure of only one of the treatments to
preexisting cells.
