What does the textbook recommend that corporate leaders should do with the organizational grapevine?

A) Try to use the grapevine as a channel of communication from executives to employees as much as possible because of its high speed and low cost.
B) Use the grapevine as a signal of employee anxiety and view it as a valid competitor to the company's formal communication system.
C) Use the grapevine when the communication requires high media richness, but otherwise use town hall meetings when communicating with employees.
D) Make every effort to destroy the grapevine, including firing employees who actively support it.
E) The textbook does not make any recommendations about what corporate leaders should do with the grapevine.