Determine if the matrix below is invertible. Use as few calculations as possible. Justify your answer. 4 2 3 6 Choose the correct answer below. Q A. The matrix is not invertible because its determinant is zero. O B. The matrix is invertible because its determinant is not zero. 0 C. The matrix is invertible because its columns are multiples of each other. The columns of the matrix form a linearly dependent set. 0 D. The matrix is not invertible because the matrix has 2 pivot positions