Marcus grew three rosemary plants. He put one in direct sunlight, one in the shade, and one in the
dark. The plant in the sun grew the most quickly
and looked the healthiest. Marcus concluded that
rosemary plants grow best in the sun.
How would you evaluate Marcus's conclusion?
O A. His conclusion is valid because his
experiment included a control.
B. His conclusion is valid because he tested
only one variable.
O C. His conclusion is flawed because he did
not perform enough trials.
O D. His conclusion is flawed because it is
based on the appearance of the plants.