$(-17)-16=-33$, so the answer is $C$. 
Which number has to be subtracted from $-17$ in order to obtain $-33$? (2017 Math Kangaroo Problem, Level 7-8, Question \#3) 
[A] $$-50$$ 
[B] $$-16$$ 
[C] $$16$$ 
[D] $$40$$ 
[E] $$50$$ 