The correct response to explain how one object can have greater kinetic energy than the other, despite both having equal masses and being in motion, is: One object has a greater speed than the other object.
Kinetic energy (KE) is calculated using the formula: \( KE = \frac{1}{2}mv^2 \), where \( m \) is the mass and \( v \) is the speed of the object. Since both objects have equal masses, the object with the greater speed will have greater kinetic energy.