Final answer:
The lamp's light that would be absorbed least by the chlorophyll pigment is the green light since chlorophyll a and b absorb primarily in the blue and red regions and reflect green light. Plant A under blue light should grow the most, followed by Plant C under orange light, and Plant B under green light would grow the least.
Step-by-step explanation:
The subject of the question is Biology, specifically dealing with the absorption spectra of photosynthetic pigments like chlorophyll a, chlorophyll b, and carotenoids such as ß-carotene in plants. Chlorophyll pigments are responsible for capturing light energy to perform photosynthesis, a process in which plants convert light energy into chemical energy. The absorption spectrum of these pigments shows that chlorophyll a and b absorb light primarily in the blue and red regions of the spectrum and reflect green light, which is why plants appear green. Therefore, the lamp emitting light in the green spectrum would be absorbed the least by chlorophyll pigments, since they reflect green light.
In an experiment, the growth of plants under different colored lights would depend on how well the chlorophyll pigments can absorb the light. Plants grown under blue light (Plant A) and red light (not mentioned, but implied by the absorption spectrum), would grow better than those under green (Plant B) and orange light (Plant C), as chlorophyll pigments preferentially absorb blue and red wavelengths. Hence, Plant A would likely exhibit the most growth followed by Plant C, and Plant B would show the least growth as it reflects green light and absorbs it the least.