The thousands\textquotesingle{} digit is $$2$$ and the tens\textquotesingle{} digit is $$4$$. The sum is $$6$$. 
The sum of the thousands\textquotesingle{} digit and the tens\textquotesingle{} digit of $$12345$$ is． 

[a] $$5$$ 
[b] $$6$$ 
[c] $$7$$ 
[d] $$8$$ 