Which of these organisms is known for being a tip-feeder?

The Tent Caterpillar is recognized as a tip-feeder because of its feeding habits, particularly during its larval stage. These caterpillars primarily consume the tender, young leaves and the developing shoots located at the tips of branches. This feeding behavior can significantly affect the growth and overall health of trees, especially when infestations are heavy. By feeding on the foliage and tips, they can hinder new growth and reduce the tree's ability to photosynthesize effectively.

In contrast, the other organisms listed do not exhibit the same feeding behavior. The Red Ring Worm is typically associated with soil and plant interactions but doesn't feed in the same manner as the Tent Caterpillar. Fusiform Rust is a fungal disease that targets specific tree species and disrupts their health but is not a feeding organism, while Oak Wilt is a vascular disease that affects oak trees, causing them to wilt and die but not through direct feeding. Understanding these differences helps clarify why the Tent Caterpillar is specifically categorized as a tip-feeder among the choices provided.