The barnacles are only able to attach them selfs to surfaces in the water. Since the surface is limited, barnacles are attaching themselves to the other barnacles, crowding the rock. The muscles were not able to grow or attach themselves off the surface of the rock. Same thing with the mussels that are growing on the rock. So not only barnacles are crowding the rock, but Mussels as well are crowding the rock.
Answer:
The correct answer will be option-C
Explanation:
The plant absorbs the sunlight to perform photosynthesis which helps produce the sugar molecule used by the plants.
The plants absorb maximum sunlight at two wavelengths that are red and blue wavelength by chlorophyll and other pigments. The efficiency of photosynthesis is also measured maximum at these two active wavelengths called action spectrum.
In the given question, since the efficiency of photosynthesis has been discussed which could be measured with the production of oxygen and consumption of carbon dioxide. The experiment performed by the Engelmann showed that aerobic bacteria got concentrated in the blue and red wavelengths as the output of the photosynthesis were observed maximum.
Thus, the selected option is the correct answer.