Albedo refers to the ability of a surface to reflect sunlight. In this case, out of the options provided, snow and water act as albedos because they have high reflectivity and reflect a significant portion of sunlight.
1. **Snow**: Snow has a high albedo because it reflects a large amount of sunlight due to its bright white color and smooth surface.
2. **Water**: Water also has a relatively high albedo, especially when sunlight hits it at a certain angle. This is why you often see a bright reflection on a body of water on sunny days.
On the other hand, asphalt road and buildings have lower albedos because they absorb more sunlight rather than reflecting it.
So, to summarize, snow and water act as albedos due to their high reflectivity, while asphalt roads and buildings have lower albedos because they absorb more sunlight.
