5.3.24 A is a 3times3 matrix with two eigenvalues. Each eigenspace is one-dimensional. Is A diagonalizable? Why? Select the correct choice below and, if necessary, fill in the answer box to complete your choice. A. No. A matrix with 3 columns must have nothing unique eigenvalues in order to be diagonalizable. B. Yes. As long as the collection of eigenvectors spans set of real numbers Rcubed, A is diagonalizable. C. No. The sum of the dimensions of the eigenspaces equals nothing and the matrix has 3 columns. The sum of the dimensions of the eigenspace and the number of columns must be equal. D. Yes. One of the eigenspaces would have nothing unique eigenvectors. Since the eigenvector for the third eigenvalue would also be unique, A must be diagonalizable.