Justin Needs to Conduct and Record Interviews with Potential Customers,for

Justin needs to conduct and record interviews with potential customers,for a recently launched product.Which of these suggestions would you give him?

A) Focus generally on open-ended questions and provide the questionnaire before recording.
B) Focus generally on closed questions and these need not be recorded.
C) Use surveys to ask questions that include descriptors such as "often" or "frequently".
D) Never confuse the customer with both open and close questions.
E) Ask open-ended and closed questions but record with permission.