A is a $3 \times 3$ matrix satisfying $\mathrm{A}^3-5 \mathrm{~A}^2+7 \mathrm{~A}+\mathrm{I}=0$. If $\mathrm{A}^5-6 \mathrm{~A}^4+12 \mathrm{~A}^3-6 \mathrm{~A}^2+2 \mathrm{~A}+2 \mathrm{I}=l \mathrm{~A}+m \mathrm{I}$, then $l+m=$

• Correct answer
  A

  5
• B

  -1
• C

  4
• D

  2

Hence, the correct answer is option: 'A'.