Which of the Following Should Be Followed When Granting an Adjustment

Which of the following should be followed when granting an adjustment?

A) You should avoid admitting that it was your company's fault.
B) You should explain what is being done to correct the situation.
C) You should use negative words to describe what went wrong.
D) You should make the customer's complaint the focus of your message.
E) You should include an apology at the end of the message.