Answer
See below
Work Step by Step
Matrix $C$ is obtained by permuting the last two columns of matrix $B$ and multiplying the first one by four. Then we need to find the determinant of matrix $C$.
Let's call the matrix that results from permuting the last two columns of matrix $B$ $B_1$. Then we have $det(B_1)=-\det B=-(-4)=4$
Let's multiply the first column's elements by four. Matrix $C$ is the resultant matrix. The property of the determinants dictates that
$\det(C)=4\det(B_1)=4.4=16$.
As a result, the determinant of the matrix $C$ is $\det (C)=16$
