Answer
B is the inverse of A.
Work Step by Step
When there is an inverse of a matrix $A A^{-1}$ = I (the Identity Matrix)
AB = $\begin{bmatrix}
2(3) + 1(-5) & 2(-1) + 1(2) \\
5(3) +3(-5) & (5)(-1) + 3(2)\\
\end{bmatrix}$ = $\begin{bmatrix}
1 & 0\\
0 & 1
\end{bmatrix}$
Since AB equals the identity matrix, B is the inverse of A.
