Final answer:
The material in Saturn's rings is suggested to be young based on several lines of evidence. The mass and structure of the rings, observations of the fine structure by the Cassini mission, and the existence of the E Ring associated with Enceladus all point to relatively young and continually changing ring material.
Step-by-step explanation:
The evidence that suggests the material in Saturn's rings is young can be seen in the mass and structure of the rings. The main rings of Saturn have a mass similar to that of the inner moon Mimas, indicating that they could have formed from the break-up of a Mimas-sized moon early in the solar system's history.
Another piece of evidence is the fine structure observed in the rings by the Cassini mission. The presence of condensations or small moons embedded in the rings produces characteristic waves, which can be photographed by Cassini. The observation of these waves and the range of changes seen in the rings suggest that the material is relatively young and continually changing.
Additionally, the existence of the E Ring, which is associated with Saturn's small icy moon Enceladus, also supports the idea of young ring material. The ongoing existence of the E Ring suggests that it is being continually replenished by a source at Enceladus, indicating geological activity in the past few million years.