Jean berko is associated with an experiment where she used fictional words to see if children could apply rules by not relying on past instances of hearing a word. this was called the test.

WUG test is the correct answer.

Jean Berko Gleason was a Psycholinguist professor at Boston University who made many contributions to the studies of language acquisition in English-speaking children. In 1958, Jean Berko created the WUG test which consists of questions that help to see the child's understanding of plural-formation, verb conjugation and the possessive. In the experiment, she used fictional words to see if the kids were still capable of applying rules without relying on past instances of hearing the word.