Answer: Choice A) 3x3
The 3x3 refers to the number of rows and the number of columns in that order.
As another example, this matrix
[tex]\begin{bmatrix}1 & 7 & 9\\13 & 41 & 2\\5 & 8 & 7\\92 & 3 & 5\end{bmatrix}[/tex]
is a 4x3 matrix because it has 4 rows and 3 columns.
