Correct Answer: option (D)Matter waves are waves associated with every moving particle and therefore are neither mechanical nor electromagnetic waves.These waves have \\\\(\\lambda = h\ imes p\\\\)Where \\\\(\\lambda\\\\) is the wavelength, \\\\(h\\\\) is plank's constant, and \\\\(p\\\\) is the particle’s moment. Therefore, matter waves are neither mechanical nor electromagnetic waves.