Final answer:
Multiple changes to VHD files should be inserted sequentially to prevent conflicts and ensure stability. Simultaneous changes can be made if the changes affect different parts and are properly merged afterwards.
Step-by-step explanation:
When making multiple changes to the image within each of the VHD files, the changes should ideally be inserted sequentially. This ensures that each change is built upon a stable version of the image, preventing conflicts and ensuring that the changes are tracked correctly. Inserting changes simultaneously can lead to conflicts, especially if two changes affect the same portion of the image. However, depending on the workflow and version control systems in place, it might be possible to work on different parts of the image simultaneously, as long as the changes get merged correctly afterwards. Randomly inserting changes is unadvisable as it can cause confusion and errors in the final image. Periodically inserting changes suggests a scheduled approach, which may work for routine updates, but not necessarily for active development or when immediate responses to issues are needed.