When three different numbers from the set $\{ -3, -2, -1, 4, 5 \}$ are multiplied, the largest possible product is 
$\text{(A)}\ 10 \qquad \text{(B)}\ 20 \qquad \text{(C)}\ 30 \qquad \text{(D)}\ 40 \qquad \text{(E)}\ 60$
First we try for a positive product, meaning we either pick three positive numbers or one positive number and two negative numbers.
It is clearly impossible to pick three positive numbers.  If we try the second case, we want to pick the numbers with the largest absolute values, so we choose $5$, $-3$ and $-2$.  Their product is $30\rightarrow \boxed{\text{C}}$.