Which feature in macOS must be used to access AirDrop from within apps?

The Share button is the correct feature to use for accessing AirDrop from within apps on macOS. This button is commonly integrated into various applications, allowing users to share content easily with nearby devices that are AirDrop-capable. When you click the Share button, you're presented with options on how you want to share the selected content, and AirDrop is typically one of the primary methods available in this menu.

In terms of functionality and user interface, the Share button offers an intuitive way to quickly access sharing options without having to navigate through multiple menus. It enhances the user experience by enabling a seamless interaction with other Apple devices, streamlining the process of sharing files, images, links, and more.

Other choices, such as the File menu and Sharing pane in System Preferences, do not directly provide AirDrop functionality within application interfaces. The App settings menu is also focused more on the configuration of the app itself rather than sharing features. Therefore, the Share button stands out as the dedicated option for utilizing AirDrop across various macOS applications.