Question

in a middle school lab, mrs. johnson gathered her students for an exciting project: exploring how moisture levels affect earthworm movement. students set up containers with different moisture levels: dry, moist, and waterlogged. they placed one earthworm in each container. they used the same type and size of earthworm in each. they used the same type of soil, but changed the amount of water added to each container.
over a week, they measured how far the worms burrowed. the earthworm in dry soil barely moved, while the one in waterlogged soil struggled, but the one in moist soil thrived burrowing the farthest.
students set up the following containers with 1 earthworm in each:
a: 2 gallons of potting soil
b: 2 gallons of potting soil, 500 ml of water
c: 2 gallons of potting soil, 1,000 ml of water
which container is the control group?
a
b
c

Explanation:

In an experiment, the control group is the one that does not receive the treatment (in this case, the change in moisture level). Container A has only potting soil with no added water, representing the baseline or normal condition for comparison with the other containers that have added water.

Answer:

A. 2 gallons of potting soil