I don't understand this statement, and would like to know more about what the question actually was, what the answer actually was, and who provided the answer. It has been some time (13 years) since Knowledge Reviews needed to be handed in; all the instructor needs to do is ascertain and note that the KR was completed. No copies or originals needed. See Traning Bulletin 3rdQ 2006. No change to this seems to have been published.
Knowledge Review Administrative Option:
Retain or Document Diver Mastery
PADI Scuba Diver, Open Water Diver, Adventures in Diving, Rescue Diver and Divemaster course standards require you to review completed course knowledge reviews with student divers to assure mastery of the information. For most courses, PADI standards also require you to collect and physically retain the knowledge reviews.
Effective immediately, you have a choice — to either retain knowledge reviews as before, or, document in the student training record that you reviewed the completed knowledge reviews and had the diver sign the knowledge reviews verifying understanding. This change aligns knowledge review documentation options with the PADI Scuba Diver and Open Water Diver course standards (as announced in the Fourth Quarter 2005 Training Bulletin).
Adventures in Diving, Rescue Diver and Divemaster course instructor guides will be revised to allow you to document diver mastery and review of knowledge reviews (rather than physically retaining them) as an option.