Which of the Following Sentences Is the Most Appropriate to Use

Multiple Choice

Which of the following sentences is the most appropriate to use at the beginning of an indirect claim message?

A) You must find a solution to this problem because it has repeatedly disappointed me.
B) I would like to put forth a very serious complaint against your substandard services.
C) We received our lawn mower on December 24.
D) Based on my negative experience with your services, I demand a refund.
E) You have not delivered your goods in proper condition.