According to the theory of evolution, why might we call some parts of the brain the old brain and some parts the new brain?

A. Old brain parts are what exist in very young children, and the new brain develops later.
B. The old brain developed first according to evolution.
C. The old brain becomes more active as we grow older.
D. The new brain deals with new information, while the old brain deals with information gathered when we were children.

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