Question

when a diagram is used to illustrate an idea, it is meant to: show or explain the idea visually; confuse the reader with extra details; hide the main point of the idea; make the idea harder to understand

Explanation:

Diagrams are visual - aids. Their purpose is to present information in a more accessible and understandable way. They simplify complex ideas by showing them visually.

Answer:

Show or explain the idea visually