All but Which of the Following Have Been Put Forth

Multiple Choice

All but which of the following have been put forth as criticisms of Piaget's theory?

A) He observed far too many children to be able to draw any reasonable conclusions.
B) He underestimated abilities of younger children.
C) Development is variable from child to child and does not always progress identically.
D) He did not take cultural differences into account.
E) He failed to account for changes in cognitive development that occur across different stages.