You can ask any question you want but you should ensure that it is a question that the customer can easily quantify and respond to. Also you need to ensure that the question(s) you ask provide meaningful data for you to make business decisions. Questions like “Please rate your overall satisfaction” or “Did the customer executive meet all your expectations?”
Do not ask questions that can be identified by negative feedback reasons. Questions such as “Was the customer executive on time?” is easily identified in the earlier mentioned question with “Customer Executive was late” in the reasons for poor feedback.