Find the Value of the Determinant $$\left| \begin{array} { l l } 1 & 2 \\2 & 1\end{array} \right|$$

Multiple Choice

Find the value of the determinant.
- $$\left| \begin{array} { l l } 1 & 2 \\2 & 1\end{array} \right|$$

A) $- 3$
B) 3
C) 5
D) 0