Which one of the following sets is arranged in decreasing order? 
选项为:A:$$7510$$, $$7020$$, $$6990$$, $$6750$$  B:$$6830$$, $$8310$$, $$9040$$, $$7990$$  C:$$5870$$, $$6840$$, $$6820$$, $$5470$$  D:$$8490$$, $$8790$$, $$9480$$, $$9740$$  请回答其中一个选项.