Pick up the correct statement from the following. The kinetic energy of a body A. Before impact is equal to that after impact B. Before impact is less than that after impact C. Before impact is more than that after impact D. Remain constant

The correct answer is: A. Before impact is equal to that after impact.

Kinetic energy is the energy of motion. It is calculated by multiplying the mass of an object by the square of its velocity. The kinetic energy of a body before impact is equal to that after impact if there is no loss of energy due to friction or other forces.

Option B is incorrect because the kinetic energy of a body can only be less than that after impact if there is a loss of energy due to friction or other forces.

Option C is incorrect because the kinetic energy of a body can only be more than that after impact if there is an increase in energy due to friction or other forces.

Option D is incorrect because the kinetic energy of a body can change if there is a change in its mass or velocity.