Concept:The early Qur'an was preserved in memory and on the writing materials available in Arabia at that time.Explanation:Paper was not widely used in Arabia during the initial period of revelation.The companions of the Prophet memorised the Qur'an fully.It was also written on available surfaces such as leather, flat stones, bones, and similar materials.Paper came into common use among Muslims only at a later stage.Hence, paper was not one of the original means of preservation.Answer:D. paper