Modigliani and Miller (M&M)Proposition II States

Modigliani and Miller (M&M) Proposition II states:

A) the cost of equity does not change when a firm takes on a greater proportion of debt.
B) the cost of equity increases when a firm takes on a greater proportion of debt.
C) the cost of debt increases when a firm takes on a greater proportion of equity.
D) the cost of equity decreases when a firm takes on a greater proportion of debt.