Diagonalize the following matrix. One eigenvalue is ). = 4 and one eigenvector is ( - 3, 1,2). -5 - 18 6 3 10 - 2 12 Select the correct choice below and, if necessary, fill in the answer box to complete your choice. O A. -30 0 For P = , D= 040 0 04 (Type an integer or simplified fraction for each matrix element.) OB. -4 0 0 For P = , D= 0 -40 0 0 4 (Type an integer or simplified fraction for each matrix element.) O C. The matrix cannot be diagonalized