What can the melting glaciers indicate about the formation of Niagara Cave?

The melting glaciers provide critical insights into the geological processes that led to the formation of Niagara Cave. During the last Ice Age, massive glaciers covered large portions of North America. As these glaciers melted, they released substantial amounts of water, which flowed over the landscape. This flowing water played a significant role in the development of the cave system by eroding and filling existing cracks and fissures in the ground, creating underground passageways over time.

When glacial meltwater inundated the area, it worked its way into the subsurface, gradually dissolving soluble bedrock, such as limestone, which is often associated with karst topography where caves commonly form. The movement of water into these natural fractures not only shaped the cave's structure but also contributed to its unique formations.

The other options focus on processes that are not directly related to the cave's formation. While melting glaciers can lead to the creation of water bodies, this option doesn't specifically explain the cave's development. Similarly, the formation of new rock layers and triggering volcanic activity are unrelated to the direct processes of cave formation driven by glacial activity. Hence, the response regarding filling cracks in the ground aligns most closely with the necessary geological processes involved in the creation of Niagara Cave.