$$\dfrac{1}{2}$$ of the pens in a box are red, $$\dfrac{1}{4}$$ of the remainder are blue and the rest are green. What percentage of the pens in the box are green? 
选项为:A:$$12.5\textbackslash\%$$  B:$$25\textbackslash\%$$  C:$$37.5\textbackslash\%$$  D:$$75\textbackslash\%$$  请回答其中一个选项.