There are $$40$$ guests queueing to enter a party. Every $$4^{\rm th}$$ guest in the queue receives a balloon and every $$6^{\rm th}$$ guest in the queue receives a mask. How many guests receive both a balloon and a mask?~\uline{~~~~~~~~~~}~ 
选项为:A:$$2$$  B:$$3$$  C:$$4$$  D:$$5$$  请回答其中一个选项.