In the following nuclear reaction,
$D\stackrel{\alpha }{\to }{D}_1\stackrel{{\beta }^{-}}{\to }{D}_2\stackrel{\alpha }{\to }{D}_3\stackrel{\gamma }{\to }{D}_4$
Mass number of $D$ is $182$ and atomic number is $74$ . Mass number and atomic number of $D_4$ respectively will be

• Correct answer
  A

  $174$ and $71$
• B

  $174$ and $69$
• C

  $172$ and $69$
• D

  $172$ and $71$

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