How can this be avoided?

It is possible to a user to forward calls to a long distance number, incurring unapproved charges to the organization. How can this be avoided?

A.
Limit the translation digits in the Call Forward Configuration page.

B.
Attach a special device pool to the Call Forward Configuration page.

C.
Create an appropriate route plan for the Directory Number Configuration page.

D.
Apply an appropriate calling search space to the Directory Number Configuration page.