What type of structure allows for new plant formation through rooting?

The correct answer pertains to nodes on stolons because these nodes are specialized structures that enable vegetative reproduction in certain plants, particularly in aquatic environments. Stolons are horizontal connections that grow along the surface of the substrate, and the nodes are points where new shoots or roots can form. When these nodes come into contact with suitable substrate conditions, they can establish new plants by developing roots into the soil or substrate.

In contrast, roots mainly serve the function of anchoring the plant and absorbing water and nutrients. While they can also be involved in vegetative reproduction, they do not directly contribute to new plant formation through rooting in the same way nodes do.

Flowers play a critical role in the reproductive cycle of flowering plants but are predominantly involved in sexual reproduction, facilitating pollination and seed production rather than direct plant propagation through rooting.

Leaves are essential for the process of photosynthesis and can sometimes store energy, but they do not function as sites for new plant formation through rooting.

Thus, nodes on stolons are key to vegetative propagation, making them the most relevant answer regarding new plant formation through rooting.