What element is located

Answer:
Option A. (-1)
Step-by-step explanation:
We should always remember an element of a matrix is always represented in (row.column) form.
It means when we have to show an element [tex]a_{12}[/tex] , it means the given element is located in the matrix at first row and second column.
Now we come to the question the given element [tex]b_{31}[/tex] is located in 3rd row and 1st column of the matrix.
Here [tex]b_{31}=(-1)[/tex]
Therefore answer will be (-1) Option A.