The correct statement about the change that lava undergoes is: The lava can cool back into rock.
When magma from inside the Earth erupts and reaches the surface, it is called lava. Upon cooling, lava solidifies and can form igneous rock. The other statements are incorrect: the mass of lava does not change significantly during its transition from solid to liquid; it does not burn into smoke, as lava is molten rock and not a gaseous material; and it does not lose mass in the process.