To produce 1 metric ton of coal, up to 30 metric tons of earth must first be removed or stripped. Some strip mines produce up to 50,000 metric tons of coal a day. How many metric tons of earth must be removed in order to mine 50,000 metric tons of coal?
A. 250,000,000 metric tons
B. 1,500,000 metric tons
C. 30,000 metric tons
D. 1,500 metric tons