[单选题]
A beam of monochromatic light is incident on a single slit. After passing the slit, a diffraction pattern is observed on a screen of distance D to the slit.
Which of the following is correct for the diffraction pattern observed on the screen when the D is doubled?
A. The width of the central maximum is halved.
B. The angular width of the central maximum is halved.
C. The angular width of the central maximum does not change.
D. The angular width of the central maximum is doubled.
