Refer to the Figure Showing the Results of Bjorkman and Colleagues

Multiple Choice

Refer to the figure showing the results of Bjorkman and colleagues' studies of plant responses to different light levels. The plants were reared at three different levels of light: high (red line) , medium (blue line) , and low (green line) . The acclimatized plants were then subjected to various light levels, and their ability to photosynthesize was measured.
At the light intensity of 1,500 μmol/m²/s, which plants are light-limited?

A) Those acclimatized to high-intensity light
B) Those acclimatized to medium-intensity light
C) Those acclimatized to low-intensity light
D) None; they have all reached the light saturation point.