Which One of the Following Best Illustrates Piaget's Concept of Accommodation

Which one of the following best illustrates Piaget's concept of accommodation?

A) Anne is given 10 more addition problems when she does the first 10 carelessly.
B) Gabrielle writes down her definition of a mollusk-something she learned word for word from a textbook.
C) Aaron copies down what his teacher writes on the blackboard.
D) Karl revises his understanding of what clouds are like when he studies them in science.