[单选题]
The angle of incidenck;e/g ;6v ypmqh lq8h-:bt 6yb vdoh s)6d1f( h+qt,kce
A. must equal the angle of reflection.
B. is always less than the angle of reflection.
C. is always greater than the angle of reflection.
D. may be greater than, less than, or equal to the angle of reflection.
