Which of the Following Is True About the Neural Control

Which of the following is true about the neural control of waking?

A) The cortex must begin the waking process and send signals to lower brain areas that are involved in arousal.
B) The brain stem must begin the waking process and send signals to higher brain areas that are involved in arousal.
C) The midbrain, by itself, controls the waking process.
D) There are arousal centers in both the brain stem and the forebrain that coordinate waking with other brain areas.