A function, $\lambda$, is defined by
$\lambda \left ( p,q \right )=\left\{\begin{matrix} \left ( p-q \right )^{2} , & \text{if} \:p\geq q, \\ p+q, &\text{if} \: p< q.\end{matrix}\right.$
The value of the expression $\dfrac{\lambda \left ( -\left (- 3+2 \right ),\left ( -2+3 \right ) \right )}{\left ( -\left ( -2+1 \right ) \right )}$ is:
- $-1$
- $0$
- $\frac{16}{3}$
- $16$