对于任意的整数$$n\left( n{\geqslant }2 \right)$$，满足$${{a}^{n}}=a+1$$，$${{b}^{2n}}=b+3a$$的正数$$a$$与$$b$$的大小关系是(  )
选项为:A:$$a\textgreater b\textgreater1$$  B:$$b\textgreater a\textgreater1$$  C:$$a\textgreater1$$，$$0 \textless{} b \textless{} 1$$  D:$$0 \textless{} a \textless{} 1$$，$$b\textgreater1$$  请回答其中一个选项.