The Widths of the Lines Produced by Monochromatic Light Falling

Multiple Choice

The widths of the lines produced by monochromatic light falling on a diffraction grating can be reduced by:

A) increasing the wavelength of the light
B) increasing the number of rulings without changing their spacing
C) decreasing the spacing between adjacent rulings without changing the number of rulings
D) decreasing both the wavelength and the spacing between rulings by the same factor
E) increasing the number of rulings and decreasing their spacing so the length of the grating remains the same