Answer:
C) three-letter nonsense words
Explanation:
Ebbinghaus explained in his theory of memory and forgetting, that the memory of a person decreases over time if it is un-learned. He believed that a person starts losing his or her memory in a matter of days or weeks unless it is being revised. He found that a person forgets more frequently just after learning rather than recalling it over time. He used non-sense syllables in his memory research because he was interested in understanding how memories were formed. So, he decided to take pure material, uncontaminated by previous learning.
