**Question:**

If $A, B$ are square matrices of order $3, A$ is non-singular and $A B=0$, then $B$ is a

(a) : matrix

(b) singular matrix

(c) unit-matrix

(d) non-singular matrix

**Solution:**

(a) : matrix

Since *A* is non-singular matrix and the determinant of a non-singular matrix is non-zero, *B* should be a : matrix.