THANK YOU FOR FILLING QUESTIONNAIRE: SUGGESTIONS CONSIDERED
Thank you for filling and returning our questionnaire. I wish to take this opportunity to tell you that I have brought your comments to the attention of [PERSON/POSITION, ex. our vice president of sales]. [STATE ACTION TO BE TAKEN, We have immediately called a meeting to discuss the possibility altering our terms of sale, as you suggested.]
Again, I thank you for your response and I will keep you posted on the results.