Luis has 7 apples and 2 bananas. He gives 2 apples to Yuri who, in return gives bananas to Luis. Then Luis has as many apples as bananas. How many bananas did Yuri give to Luis? 
选项为:A:$$2$$  B:$$3$$  C:$$4$$  D:$$5$$  E:$$7$$  请回答其中一个选项.