A $$12$$-metre long steel pipe was cut into few pieces. The length of each piece is $$3$$ metres. It takes $$18$$ minutes to complete the whole process. How long does it take to cut a $$12$$-metre pipe into $$6$$-metre sections? 
选项为:A:$$6$$ minutes  B:$$9$$ minutes  C:$$12$$ minutes  D:$$18$$ minutes  E:None of the above  请回答其中一个选项.