Final answer:
The color of green grass is mainly determined by the selective absorption and reflection of sunlight; chlorophyll absorbs red light and reflects green light, which is why grass appears green.
Step-by-step explanation:
The color of green grass is influenced by the processes of reflection, absorption, refraction, and transmission of light. Green grass appears green because the chlorophyll molecules within the grass blades absorb wavelengths of light in the red portion of the visible spectrum, while strongly reflecting the green wavelengths. As a result of this selective absorption and reflection of light, we observe grass as green. The reflected green light is what contributes to the color we perceive.
Moreover, when light goes through a medium such as the grass blades, some of the light is transmitted and some may be refracted, with different wavelengths bending by different amounts depending on the material's refractive index. However, the transmission and refraction do not significantly alter the perceived color of the grass, as they do not change the spectral composition of the reflected light that reaches our eyes. Finally, due to the rough surface of grass, some scattering of light occurs, but it is not the primary factor in determining the color of grass.