The sum of Ben\textquotesingle s age and Ben\textquotesingle s grandma\textquotesingle s age is $$96$$. Ben\textquotesingle s grandma\textquotesingle s age is three times older than Ben\textquotesingle s age. How old is Ben\textquotesingle s grandma? 
选项为:A:$$24$$  B:$$48$$  C:$$72$$  D:$$96$$  请回答其中一个选项.