Final answer:
The dominant directional forces in Degas' Jockeys Before the Race are diagonals, which are created through the use of lines and colors to convey motion.
Step-by-step explanation:
In Degas' Jockeys Before the Race, the dominant directional forces are diagonals. Degas used lines and colors to convey the motion of people and animals in the painting. There is a strong zigzag that brings the viewer's eye from top to bottom or bottom to top, creating a sense of movement and energy.