Sally and Maria hypothesized that earthworms lived only in dark, damp places. They measured a one-meter square in a shady spot near a stream. They dug through the soil and collected earthworms. They collected 43 worms. What should the girls do to reach a
valid conclusion for their hypothesis?
A)
Repeat the experiment in another shady spot.
B)
Nothing. They carried out a valid experiment.
Repeat the their steps in different locations, including sunny, dry, and wet.
D)
Repeat the dig on a larger area near the stream.