The correct response is:
It tells what happened and why, which can lead to greater understanding about an idea or event.
This answer accurately captures the essence of cause-and-effect text structure by emphasizing how it explains not just the events (what happened) but also the reasons behind those events (why it happened). This structure not only clarifies relationships between events but also enhances the reader's comprehension of the overall context and significance of the ideas presented. It helps to connect causes with their effects, leading to a deeper understanding of the topic being explored.