You can decrease the kinetic energy of an object as much as you want. You can do so by either reducing mass by half or reducing the speed by half. Which option would you pick, and why ?

Explanation

Reducing the speed `(upsilon)` by half, KE will become `(1//4)th` of the its previous value and hecne will be reduced by `(3//4)`, whereas reducing the mass (m) by half will rreduce the kinetic energy only by half.