Which of the following is the most effective caption for a figure?

The most effective caption for a figure provides a clear and concise description that not only labels the figure but also gives enough context for the viewer to understand its content without needing additional information.

The selected option does a commendable job by specifically stating that the figure illustrates the three levels of the certification program. It effectively captures the essence of the diagram by highlighting its primary focus, enabling the viewer to quickly comprehend the key message the figure is conveying.

In contrast to the other options, this caption is succinct while still informative, ensuring that it serves its purpose as a title and description. It straightaway indicates what the viewer can expect to see, which is crucial for enhancing understanding and engagement with the figure. Other choices, though descriptive, may contain extraneous details or not convey the core subject of the figure as effectively.