The Demand Curve for Low-Skilled Labor Lies to the Left

The demand curve for low-skilled labor lies to the left of the demand curve for high-skilled labor because

A) there are more high-skilled workers than low-skilled workers.
B) high-skilled workers require more compensation than low-skilled workers.
C) high-skilled workers are more productive than low-skilled labor.
D) firms do not see any difference between high-skilled labor and low-skilled labor.