PLEASE HELP 50 POINTS + BRAINLIEST TO THE CORRECT ANSWER The data show the growth of two bean plants over several weeks using four different fertilizers. The experimental data would be more valid of which of the following variables was included in the experiment?

a. A fifth fertilizer was tested.

b. Only one plant was tested.

c. The plants were grown at variable temperatures.

d. A control without fertilizer was included for each plant.

(The data is in the image)

Azoologist is studying four very closely related feline species. she wishes to compare their gestation periods. an observational study is conducted where the zoologist observes the gestation period of 50 randomly selected felines in each species. a one-way anova test is run to test the hypothesis that the average gestation period is the same for each of the four species. a level of significance of 0.05 is used, and a p-value of 0.01 is calculated. based on this result, the conclusion that can be drawn is that: