forming a theory designing a model analyzing data comparing to a control
I gave my students this multiple choice question: Ancient Greeks hypothesized that a hair from a horse's tail left in water would turn into a worm. What scientific process most likely would have disproved this hypothesis?

Only one answer is correct among these 4 choices:
- forming a theory
- designing a model
- analyzing data
- comparing to a control

Could you tell me which one is correct?

comparing to a control