When designing a report for mobile users, it is important to consider the variability in screen sizes and resolutions. Using a fixed size for objects would not adapt well to different devices. Setting all objects to Portrait view does not inherently provide better usability for mobile users because some mobile devices may benefit from landscape views as well. Setting margins between objects in the report could help with spacing, but it does not address the adaptability to different screen sizes. Sizing the objects as a percentage of the available space allows the report to dynamically adjust and resize based on the specific device's screen, ensuring that the content is accessible and readable across various devices. Therefore, using percentage sizes for objects is the most effective approach.