Which of the Following Best Describes What Is Meant by a "Depth

Which of the following best describes what is meant by a "depth of processing account"?

A) Social stimuli is processed at greater mental depth because it activates a number of different concepts
B) Information that is potentially self-threatening is processed more superficially in a form of psychological self-defense
C) Memory of self-relevant or self-referential information is facilitated because it leaves a more interconnected, enduring memory trace
D) The older the memory, the deeper it is buried within neural networks, making it harder/slower to retrieve