Which One of the Following Conclusions Can Be Derived from Recent

Which one of the following conclusions can be derived from recent research regarding Piaget's theory of cognitive development?

A) Middle school and secondary school students typically have an easier time thinking logically in the social sciences than they do in the physical and life sciences.
B) Students will think more logically about a topic when they have acquired relevant knowledge and experiences related to the topic.
C) Many students continue to show signs of preoperational thinking until well into the high school years.
D) Students have an easier time understanding fractions and proportions later on if such concepts are first introduced at the same time that division is introduced (e.g., in third grade) .