A hot-air balloon is rising vertically with a constant velocity of $10 \mathrm{~m} / \mathrm{sec}$. An object is dropped from the balloon when it is 60 m above the ground. The angle of elevation of the Sun is $45^{\circ}$. When the falling object is 33.75 m from the ground, the rate at which the shadow of the object is traveling along the ground is (take $g=10 \mathrm{~m} / \mathrm{sec}^2$ )

• A

  $15 \mathrm{~m} / \mathrm{sec}$.
• B

  $20 \mathrm{~m} / \mathrm{sec}$.
• Correct answer
  C

  $25 \mathrm{~m} / \mathrm{sec}$.
• D

  $30 \mathrm{~m} / \mathrm{sec}$.

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