Which of the Following Is True of Acknowledgements

Which of the following is true of acknowledgements?

A) One must not use the you-viewpoint when writing acknowledgements.
B) One must use a highly formal style when writing acknowledgements.
C) Acknowledgements are typically written using the indirect plan of organizing information.
D) The sole purpose of writing acknowledgements is to help build goodwill.
E) Acknowledgements let people who order goods know the status of their orders.