A beam of light travels from air into a glass block. The critical angle is $42^{\circ}$. Which statement is correct?
- AThe angle of incidence is the angle between the ray of light and the surface of the glass block.
- BThe angle of incidence is always bigger than $42^{\circ}$.
- CThe angle of refraction cannot be less than $42^{\circ}$.
- DThe angle of refraction is smaller than the angle of incidence.