What is an example of a hypothesis leading to a new experiment?

a. upon seeing bacteria under the microscope, scientists theorized that they could be the cause of illness.
b. galileo dropped different balls off of the leaning tower of pisa to explain how things with different weights fall at the same speed.
c. galileo had the idea that objects of different weight will fall at the same speed. he tested this by dropping different balls off of the leaning tower of pisa.