A vertical spring with force constant $k$ is fixed on a table. A ball of mass $m$ at a height $h$ above the free upper end of the spring falls vertically on the spring so that the spring is compressed by a distance $d$. The net work done in the process is

• Correct answer
  A

  $m g(h+d)-\frac{1}{2} k d^2$
• B

  $m g(h-d)-\frac{1}{2} k d^2$
• C

  $m g(h-d)+\frac{1}{2} k d^2$
• D

  $m g(h+d)+\frac{1}{2} k d^2$

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