क्वांटम परिकल्पना के आधार पर प्रकाश विद्युत प्रभाव की सफल व्याख्या किसने की थी?

Consider the following statements regarding the dual nature of radiation: (I) The photoelectric effect demonstrates that light energy is quantized in discrete packets (photons), and the energy depends on frequency, not intensity. (II) The interference and diffraction phenomena prove that light cannot be treated as particles alone; it exhibits wave properties. (III) The energy of a photon can be increased by increasing the intensity of incident light in the photoelectric effect. Which of the above statements are true?

Assertion (A): The minimum negative potential applied to the anode in a photoelectric experiment at which the photoelectric current becomes zero, is called the cut-off voltage. Reason (R): The threshold frequency for a metal is the minimum frequency of incident radiation below which emission of photoelectrons does not take place.