Concept:Interference and diffraction redistribute light energy without any net loss, so energy is conserved.Formula:No formula is needed for this conceptual question.Solution:Statement A is true because in interference and diffraction energy is only redistributed, not created or destroyed, obeying conservation of energy.Statement B is false because both interference and diffraction are also observed with sound waves (which are mechanical waves), not only light waves.Thus A is true and B is false.Shortcut:NoneAnswer:C. A is true, but B is false
