Which of the Following Statements About Concessions Is True

Which of the following statements about concessions is true?

A) Making a concession before the other side can present its position is an excellent way to preempt control of the meeting.
B) Concessions should gradually increase in size.
C) Once made, a concession cannot be withdrawn.
D) Be flexible, if it is necessary to abandon your objectives to get an agreement, be willing to adjust.
E) None of the above statements about concessions is true.