Question

read the following experiment story and answer the questions that follow.
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.
on the final day, they discussed their findings. “moist soil is best for worms!” one student exclaimed. they created graphs to show their results and returned the worms to a nearby garden, proud of their discovery about the importance of soil moisture for earthworms.
match each factor in the experiment below with the correct type of variable
distance burrowed by the earthworms
number of worms
soil type
temperature
soil moisture levels (dry, moist, and waterlogged)

Explanation:

In an experiment, the independent variable is what is changed, the dependent variable is what is measured as a result of the change, and controlled variables are kept the same. The distance burrowed by earthworms is measured based on soil moisture changes, so it's the dependent variable. The number of worms, soil type, and temperature are kept the same, so they are controlled variables. Soil moisture levels are deliberately changed, so it's the independent variable.

Answer:

Distance burrowed by the earthworms - Dependent variable
Number of worms - Controlled variable
Soil type - Controlled variable
Temperature - Controlled variable
Soil moisture levels (dry, moist, and waterlogged) - Independent variable