Final answer:
Chlorophyll in plants captures blue and red wavelengths for photosynthesis and reflects green. Plants with chlorophyll b absorb blue and red-orange light most effectively, harnessing the most energy from these wavelengths rather than from x-rays or infrared light.
Step-by-step explanation:
Plants use chlorophyll to capture the blue and red wavelengths of visible light and reflect the green wavelength. When plants containing only chlorophyll b are exposed to radiation with wavelengths such as 450nm (blue light) and 670nm (red light), they harness the most energy for photosynthesis during these wavelengths. The absorption spectrum of chlorophyll b shows that it predominantly absorbs blue and red-orange light. This pigment does not absorb light effectively out of the visible spectrum such as the 10nm (x-rays) or the 800nm (infrared light). As such, in the given scenario, the plants exposed to 450nm and 670nm wavelengths would harness the most energy, as these are within the optimal range for photosynthesis.