The Granite Boulders in Rocky Mountain National Park Are a Favored

The granite boulders in Rocky Mountain National Park are a favored place among talented climbers who specialize in the art of bouldering, or climbing harder (but shorter) routes without tying into a rope. Climbers have taken to (illegally) stashing foam crash pads underneath the boulders but marmots and other rodents chew up the pads and the litter is spread by the wind. The pristine National Park is most like a

A) public good.
B) private good.
C) common resource.
D) natural monopoly.