Answer:
B and D
Explanation:
Diffraction refers to the bending of waves either around an obstacle or through a gap.
A is not diffraction because although it involves the bending of light, it is due to travelling between mediums instead of bending around an obstacle or through a gap, (A is referring to refraction).
B is an example of diffraction because it is referring to the bending of the sound waves as it passes through a gap (a door) which is why it is amplified.
C is not an example of diffraction as the light waves do not bend, they simply bounce back from the mirror surface to form the image (reflection).
Finally, D is diffraction because the waves are passing though a gap in a barrier and will bend as a result due to diffraction.
Hope this helped!
