TOEFL Listening: ETS-TOEFL听力机经 - KM8PQVU4ZFT33KB5P$

The professor talks about light passing through a glass prism. What is he trying to illustrate with his example? A. The interaction between the light and atoms in the glass B. The different colors produced by light of different wavelengths C. The magnetic properties of some molecules in glass D. The process by which electric fields create magnetic fields