d. All are examples of reflection.
When waves like heat, light, or sound come into contact with a surface that doesn't absorb them, they bounce back. This phenomenon is known as reflection. Reflection can be seen in things like an echo, a mirror, and light coming through a window. When the wave hits a surface, it bounces back, allowing us to see an image, hear an echo, or see our reflection. Therefore, the correct response is option (d).