Let $A = \begin{bmatrix} 5 & 5 \alpha & \alpha \\\ 0 & \alpha & 5 \alpha \\ 0 & 0 & 5 \end{bmatrix}$ <br> If $|A^2| = 25$, then $|\alpha|$ equals :

Question

( A ) $1$
( B ) $\frac{1}{5}$
( C ) $5$
( D ) $5^2$