C 
Alina writes the numbers $1,2,\cdots ,9$ on a separate cards, one number per card. She wishes to divide the cards into $3$ groups of $3$ cards so that the sum of the numbers in each group will be the same. In how many ways can this be done? 
$$0$$ 
$$1$$ 
$$2$$ 
$$3$$ 
$$4$$ 