10.??Copper(铜)was the first metal that man learned to make.In some mountainous lands there were rocks streaked with green minerals.One day some rocks were accidentally heated by a roaring fire.When the fire burned low,little beads of copper were seen on the rock wall.After that,men heated the rock deliberately to see whether more copper would appear.They soon found a good way to make copper.They would build a trench on a hillside and fill it with charcoal and copper-bearing rock.They covered this furnace with flat stones.They started a wood fire to heat the charcoal and the hot charcoal released copper from the rock.A hot red pool of melted metal formed at the mouth of the trench.When it was cool,the solid metal could be lifted out and cut and pounded into shapes. 问题：Men shaped the copper by（ ）

A. melting it

B. pounding it

C. breaking it

D. both b and c