Which of these statements best describes the process of “continuous mining”?
A) Machines such as draglines, wheel excavators, and large shovels remove topsoil and subsoil to access coal that is found close to the surface or on hillsides.
B) Teams of miners work in shifts to make sure coal is being mined 24 hours a day.
C) Explosives are used to break up a coal seam.
D) Cutting machines work along walls of coal up to 1,000 feet long to cut coal and drop it onto a conveyor belt.
E) Machines with large, rotating cutters break into the coal and scoop it onto a built-in conveyor.