【单选题】

Questions 17 to 20 are based on the following passage.At the end of the passage you will be given 20 seconds to answer the questions.

Now listen to the passage.
How can the most effective complaint be madeA．Showing the faulty item to the manager.
B．Explaining exactly what is wrong with the item.
C．Saying firmly that the item is of poor quality.
D．Asking politely to change the item.