The Radius of the Event Horizon of a Black Hole

The radius of the event horizon of a black hole, the Schwarzschild radius:

A) is constant, because the general theory of relativity states that the size of a black hole is independent of its mass.
B) is smaller the more massive the black hole, because the matter will be more condensed.
C) will not depend on its mass but will depend on the material from which it was formed, a "hydrogen" black hole being smaller than an "iron" black hole.
D) is larger, the more massive the black hole.