The correct response is:
It tells what happened and why, which can lead to greater understanding about an idea or event.
Explanation: A cause-and-effect text structure is primarily focused on illustrating the relationship between events (causes) and their outcomes (effects). By explaining what happened (the effects) and why it happened (the causes), this structure allows readers to understand the underlying factors that contribute to specific events or situations. This understanding can deepen readers' comprehension of the topic presented, as they can see not just the events in isolation, but how they relate to and influence one another.