question_answer

Which of the following (i) Adjoint of a symmetric matrix is symmetric, (ii) Adjoint of a unit matrix is a unit matrix, (iii) \[A(adj\,A)=(adj\,A)\]\[A=\,|A|I\]and (iv) Adjoint of a diagonal matrix is a diagonal matrix, is/are incorrect

A) (i)

B) (ii)

C) (iii) and (iv)

D) None of these