The Substitution Effect on the Quantity of Labor Supplied Given

The substitution effect on the quantity of labor supplied given a change in the real wage is

A) generally positive and therefore pushes supply in the same direction as the income effect.
B) always positive and therefore pushes supply in the same direction as the income effect.
C) generally negative and therefore pushes supply in the same direction as the income effect.
D) always negative and therefore pushes supply in the same direction as the income effect.
E) none of the above.