单项选择题
3) Four trials of Young’s double-slit experiment are conducted. (a) In the first trial, blue light passes through two fine slits 400 mm apart and forms an interference pattern on a screen 4 m away. (b) In a second trial, red light passes through the same slits and falls on the same screen. (c) A third trial is performed with red light and the same screen, but with slits 800 mm apart. (d) A final trial is performed with red light, slits 800 mm apart, and a screen 8 m away. Rank the trials (a) through (d) from the largest to the smallest value of the angle between the central maximum and the first-order side maximum. In your ranking, note any cases of equality.
A．b = d > a > c
B．b > a > c = d
C．a > c = d > b
D．d > b > c > a
