Muhammad, a second grader, wants to memorize a list containing the following words: cat, chrysanthemum, horse, honeybee, snake, spider, and cactus. He categorizes cat, horse, and snake as animals; honeybee and spider as insects; and chrysanthemum and cactus as plants. Memorizing the names of these categories helps him remember the members of the categories. In this scenario, Muhammad uses a form of mnemonic device called