Sidecar is a feature that lets you use your iPad as a display that extends or mirrors your Mac desktop. You can use Sidecar to work with different apps on the different screens, use the same app on both screens, or mirror the screens so that they show the same content. You can also use your Apple Pencil to draw, edit, or mark up documents on your iPad while seeing the updates live on your Mac. Sidecar requires macOS 10.15 or later and iPadOS 13 or later on supported models. You can use Sidecar wirelessly or with a USB cable. To use Sidecar, you need to select your iPad from the Display menu in Control Center or the menu bar on your Mac, or from the AirPlay menu on macOS Catalina. You can also use the sidebar and the Touch Bar on your iPad to access common Mac controls and app-specific commands. The other options are not the correct answer, as they have different functions or are not available on macOS and iPadOS.
Universal Control is a feature that lets you use a single keyboard, mouse, or trackpad to control your Mac and iPad, with the iPad showing its own Home Screen and apps rather than the desktop and apps of your Mac. You can also drag and drop content between your devices. Universal Control requires macOS Monterey or later and iPadOS 15 or later on supported models.
Screen Sharing is a feature that lets you remotely view or control another Mac or share your Mac screen with others over the internet. You can use Screen Sharing to help someone with a problem, collaborate on a project, or access your files and apps. Screen Sharing requires macOS 10.14 or later on both Macs, and an Apple ID or a local network connection.
Stage Manager is not a feature on macOS or iPadOS. It is a feature on watchOS 8 or later that lets you control the camera and microphone on your iPhone from your Apple Watch. You can use Stage Manager to take photos, record videos, zoom in and out, adjust the exposure, mute the sound, and switch between the front and back cameras on your iPhone. References:
Apple Device Support Exam Prep Guide, page 6
Use an iPad as a second display for a Mac
Use iPad as a second display for your Mac
Sidecar: Turn an iPad Into a Secondary Mac Display
Use Universal Control on your Mac and iPad
Share the screen of another Mac
[Use Stage Manager on your Apple Watch]
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