Which statement describes the best way to determine how different levels of light affect the growth of seedling plants? Choose three different light levels, and place four identical plants under each light level to observe the light’s effect on multiple plants.

Choose five different light levels, and place one identical plant under each of the light levels for exactly one week.

Choose four different light levels, and place eight different plant types under the light levels, two under each one, and observe them every day.

Choose one type of light and one type of plant, and then observe the plant for at least four weeks, measuring it each day.