A confounding variable refers to an external effect, which modifies the influence of an independent and dependent variable. This extraneous effect is used to affect the outcome of an experimental design. The confounding variables can ruin the experiment and can generate unnecessary outcomes.
In the given case, confounding variables can be introduced by testing multiple hypotheses at a time and by using distinct kinds of soil in each of the samples.
Tad poles have gills that help them breathe underwater. frogs have lungs that help them breathe underwater. tadpoles have tails and fins to help them swim underwater. frogs have arms and legs to help them swim.
