A: $$2350$$ is even, thus it is a multiple of $$2. 2350$$ ends with $$0$$, thus it is a multiple of $$5$$ and $$10$$;  B: $$1284$$ ends with $$84$$, and $$84$$ is a multiple of $$4$$, thus $$1284$$ is a multiple of $$4$$;  C: $$9 + 9 + 7 + 2 = 27$$ is a multiple of $$9$$, thus $$9972$$ is a multiple of $$9$$;  D: $$5 + 7 + 4 + 2 = 18$$, it is a multiple of $$9$$ and $$3$$; since it ends with $$2$$, it is also a multiple of $$2$$, and thus a multiple of $$6$$;  Hence the incorrect statement is C. 
Which of the following statements is incorrect? 

a) $$2350$$ is a multiple of $$2$$, $$5$$ and $$10$$ 
b) $$1284$$ is a multiple of $$4$$ 
c) $$9972$$ is not a multiple of $$9$$ 
d) $$5742$$ is a multiple of $$6$$ and $$9$$ 