Which of the following are true statements about ozone holes? (Select the three best answers.)

A. Ozone holes don't have any ozone in them.

B. Ozone holes allow ultraviolet light to reach the Earth's surface.

C. Chlorofluorocarbons make an ozone hole larger.

D. Ozone holes have more ozone than usual.

E. Ozone holes can be hole-shaped.

F. There is always just one ozone hole in the Earth's atmosphere.