（$$2017$$ Nanyang Primary School, First Semestral Examination, Primary Three, Question \#$$9$$)  Study the number pattern below.  $$\boxed{4168}$$,~ $$\boxed{4318}$$,~ $$\boxed{4468}$$,~ $$\boxed{4618}$$,~ $$\boxed{?}$$,~ $$\boxed{4918}$$  What is the missing number? 
选项为:A:$$4518$$  B:$$4718$$  C:$$4768$$  D:$$4868$$  请回答其中一个选项.