Fred Is Having a Vivid Dream About Running in a Marathon.His

Fred is having a vivid dream about running in a marathon.His legs don't start pumping furiously in bed in order to run because:

A) Fred knows that this is just a dream and he is able to voluntarily control his muscle movements.
B) the level of arousal in the body and the activity of the brain are significantly reduced during REM sleep.
C) even though our brains are very active,we are essentially paralyzed while in REM sleep.
D) dreaming has been found to take place only in the prefrontal lobe and doesn't affect any other areas of the brain or body.