题目内容：
Questions refer to the following letter.Lasell, Inc.
676 Keenan Dr.
Fort Worth, Texas 76035
Dear Customer,
As you may be aware, Lasell has routinely received commendations for our commitment to product safety. Every item that is sold under the Lasell name is subjected to rigorous product testing. When design flaws are detected, the model is revised to eliminate the problem. In addition, our products are built from the strongest plastics to ensure that you never have a problem with a Lasell product.
In the unlikely event that products are released with previously undetected flaws, great steps are taken to ensure that every flawed item is removed from the market and replaced for eustomers.
Late last week, our exceptional quality assurance team identified a previously undetected minor flaw in the air filters in our 6000X model. Because our records show that you have recently purchased a 6000X vacuum cleaner, we want to inform you of this flaw and of your fight to return the product for a new one. Please be assured that there is absolutely no safety risk to you or any operators of the machine. However, to ensure that you are satisfied with the quality of our products, we would like to ask you to contact the Lasell store nearest to you. The store will arrange to pick up your machine at your home at a time that is convenient for you.
Our customers' satisfaction is foremost on our mind, and we want to make sure that you are not inconvenienced in any manner. A replacement vacuum cleaner will be delivered at the time of the pickup. Furthermore, customers who share in the exchange will receive a free gift in appreciation of their business.
Sincerely,
Joe Glidden
Director
Customer Satisfaction Department
Lasell, Inc.
What is the purpose of the letter? A．To introduce a policy change
B．To invite customers to an in-store event
C．To respond to a customer complaint
D．To announce a replacement plan
参考答案：
答案解析：