Five-Year-Old Marco Complains That His Slice of Cake Is Smaller

Multiple Choice

Five-year-old Marco complains that his slice of cake is smaller than Maria's, his 10-year-old sister. But she explains, "Look, your slice is skinnier, but it's taller. So we really have the same amount." Which aspect of concrete operational reasoning does Maria's explanation use?

A) decentered thought
B) seriation
C) class inclusion
D) dynamic transformation