Answer: The correct answer is "The surface of the lake is smooth".
Step-by-step explanation:
The light gets reflected from the smooth surface at the same angle as it hits that surface. If the light gets reflected in all direction from the rough surface when it hits the surface. Then, there will be diffuse reflection.
In the given problem, Leon sees a poster that shows a lake in front of a snow-capped mountain. The mountain appears upside down in the lake. Here, the water acts like a mirror. The light rays incident on the surface of the water from the mountain then the reflected rays get reflected back from the smooth surface of the lake. Here, the angle of incidence is equal to the angle of the reflection.
One can see the image of the object on the surface of the lake.
Therefore, the correct option is (A).