A heavy body and a light body have equal kinetic energy. Then:

The relationship between kinetic energy $K$ and momentum $p$ is given by the formula:
$$K=\frac{p^2}{2m}$$

Rearranging the terms for momentum, we get:

$$p=\sqrt{2mK}$$

Since both bodies have equal kinetic energy ($K$ is constant), the momentum is directly proportional to the square root of the mass ($p\propto \sqrt{m}$). Therefore, the heavier body (larger mass $m$) will have a greater momentum.