A particle $A$ is projected from the ground with an initial velocity of $\mathrm{10 }\mathrm{m}{\mathrm{s}}^{-1}$at an angle of 60^o with horizontal. From what height $h$ should an another particle $B$ be projected horizontally with velocity $\mathrm{5 }\mathrm{m}{\mathrm{s}}^{-1}$ so that both the particles collide in ground at point $C$ if both are projected simultaneously? $(\mathrm{g}=10\mathrm{m}{\mathrm{s}}^{-2})$

• A

  $10 \mathrm{m}$
• B

  $30 \mathrm{m}$
• Correct answer
  C

  $15 \mathrm{m}$
• D

  $25 \mathrm{m}$

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