Which of the following is NOT Albert Einstein’s achievement in physics? A: Theory of Relativity B: E=mc² C: Theory of Universal Gravitation D: Law of the Photoelectric Effect

Which of the following theories does not indicate a quantum phenomenon? A: Electromagnetism theory of light B: Blackbody radiation C: Photoelectric effect D: Hydrogen Atomic Spectrum

Aware(知道) that the electromagnetic theory of light failed to explain the photoelectric effect(光电效应), Albert Einstein in 1905 sough(寻找)t some other way of understanding it.