In "Adoration of the Shepherds" by Nicolaes Maes, the most accurate answer regarding the use of value in the painting would be:
C. The subject is lighter than the background to draw the viewer's eye.
This choice reflects how artists often use lighter values for focal points in a composition to attract attention. In the painting, the figures of the shepherds and the newborn Christ are depicted with lighter tones against a darker background, effectively drawing the viewer’s gaze toward the main subjects.