The role of titles on graphs is primarily to?

The primary role of titles on graphs is to indicate the subject matter being presented. A title serves as a concise description that informs the viewer about what the graph represents, such as the data being analyzed, the variables involved, or the relationship being showcased. By providing a clear title, the graph becomes more accessible and comprehensible, allowing the audience to quickly grasp the essential information it conveys.

In contrast to the other options, while aesthetic appeal and professionalism can enhance a graph's appearance, they are secondary to the informational purpose of the title. Additionally, increasing complexity for analysis would hinder understanding rather than promote it. A well-chosen title focuses on clarity and relevance, ensuring that the viewer can interpret the data effectively.