Answer:
As researchers knew that it is a faulty event the memory was of an impossible event.
Explanation:
16% of the whole group of students were able to recall meeting a Bugs bunny character. It was an impossible event as such a large number of students had not visited Disneyland. The fake memory was implanted via an advertisement where the people watching it felt that they had visited the place and shook hands with Bugs Bunny. It was a false memory spread through the medium of advertisement.