A large block of wood of mass $M=5.99 \mathrm{kg}$ is hanging from two long massless cords. A bullet of mass $m=10 \mathrm{g}$ is fired into the block and gets embedded in it. The (block $+$ bullet) then swing upwards, their center of mass rising a vertical distance $h=9.8 \mathrm{cm}$ before the (block $+$ bullet) pendulum comes momentarily to rest at the end of its arc. The speed of the bullet just before the collision is: (Take $g=9.8{ \mathrm{m} \mathrm{s}}^{-2}$)

• A

  $841.4 \mathrm{m} {\mathrm{s}}^{-1}$
• B

  $811.4 \mathrm{m} {\mathrm{s}}^{-1}$
• Correct answer
  C

  $831.4 \mathrm{m} {\mathrm{s}}^{-1}$
• D

  $821.4 \mathrm{m} {\mathrm{s}}^{-1}$

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