Question

A student wants to find out if a particular kind of plant grows better with or without potting soil. She has two identical plants. She places one plant in potting soil and sets the plant in the sunlight.

Which of the following conditions should she use for the second plant to determine the effect of soil?

Last 2 images are answer choices

Answer 1

She has to place one in the shade and one in sunlight

Answer 2

She has to place one plant in sunlight and one in shade to accurately tell the difference.