Cathy hypothesized that corn would not grow in mud. To test this hypothesis, she took corn kernels and placed 5 in mud, 3 in soil, and 2 in water. To her surprise, the kernels in the mud grew faster than the kernels in the soil. What error might have caused these unexpected results?

The seeds she planted in the mud grew quicker because the mud is holding nutrition for the corn. The soil is a good guess to make, but the mud is more dense and moist. The water wouldn't have had more nutrients than the mud, just because the mud holds breakdown matter and other things from other plants.