Which of the following is NOT included as source of humidity in this passage

A．the main source of humidity
B．the impact of humidity on our world and ourselves
C．how humidity affect our life
D．the damage humidity has done to our world

A．a feeling of distance between a writer and his or her work
B．the illusion that you are the servant of the machine
C．a sensation of power
D．a reluctance in the author to express himself or herself