Answer
The heavy object.
Work Step by Step
The momentum of an object can be expressed in terms of its KE.
$$p = mv = \sqrt{m^{2}v^{2}} = \sqrt{(2m) (\frac{1}{2}mv^{2})} = \sqrt{(2 m)(KE)}$$
We see that if 2 objects have the same KE, the more massive object has a larger momentum.