Read the following excerpt from William Faulkner's The Sound and the Fury:
As the scudding day passed overhead the dingy windows glowed and faded in ghostly retrograde. A car passed along the road outside, laboring in the sand, died away.
The author uses the word laboring to emphasize which idea?
A. the difficulty the car had in moving
B. the work that the driver had completed that day
C. the amount of time the car had been in the shop
D. the dedication of the driver to the task at hand