Let $\mathrm{P}=\left[\begin{array}{lll}1 & 2 & 3 \\ 4 & 5 & 6 \\ 7 & 8 & 9\end{array}\right]$ be a matrix. Three elements of this matrix P are selected at random. A is the event of having the three elements whose sum is odd. B is the event of selecting the three elements which are in a row or column. Then $\mathrm{P}(\mathrm{A})+\mathrm{P}\left(\frac{\mathrm{A}}{\mathrm{B}}\right)=$

• A

  $\frac{221}{420}$
• Correct answer
  B

  $\frac{17}{21}$
• C

  $\frac{21}{20}$
• D

  $\frac{3}{2}$

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