Implementation of Policies Is Often Difficult Because of All but Which

Implementation of policies is often difficult because of all but which of the following reasons?

A) The policy to be carried out is not always clearly stated.
B) Policy directives to bureaucrats sometimes leave them with too much discretion.
C) Implementation involves many different agencies and layers of government.
D) Public policy problems can be extremely complex.
E) After policies are implemented, they must still undergo the development stage.