nothing can be further simplify in this problem
We find the area of the total square which is 8in • 8in=64in^2 . Now we find the area of the small quadrilateral which is 4in•4in=16 in^2.
Now we subtract the area of the small quadrilateral from the big quadrilateral’s area 64in^2 -16in^2 leaving us with the are of 48in^2 of the figure
Let

be the identity matrix. Then pick whatever matrix you like for

.
The answer is C. It has a high density