Marko has $$9$$ pieces of candy and Tomo has $$17$$ pieces of candy. How many pieces of candy does Tomo need to give to Marko so that each boy has the same number of pieces of candy? 
选项为:A:$$2$$  B:$$3$$  C:$$4$$  D:$$5$$  E:$$6$$  请回答其中一个选项.