You can enter additional information which can be made available to the advisor who responds to your inquiry. This information cannot be disclosed until after you view the answer.
If you decide to forego providing additional information, your inquiry will still be processed. However, should you wish to provide contact information to the responding advisor after you view the answer (i.e. so they can contact you to clarify their response) and you do not provide additional information, you will have to do so of your own accord outside the Philadelphia Advisors system). In other words, additional information is gathered only as a convenience for you, and you will still have full control over whether to disclose any and all information to the advisor once you have viewed your answer.