Which gesture requires a user to announce the active element in a touch screen screen reader?

The choice of single tap as the gesture that requires a user to announce the active element in a touchscreen screen reader is correct. When a user performs a single tap on a touchscreen device, it typically selects the item or element under their finger and triggers the screen reader to announce that element. This interaction allows users with visual impairments to be aware of what they have selected, which is crucial for navigation and understanding their environment.

In touchscreen interfaces that are designed for accessibility, the feedback provided by the screen reader after a single tap enhances usability by ensuring that the user knows which item they are interacting with before taking further action. This is a vital aspect of web accessibility, as it helps users manage their interactions with content effectively.

Other gestures like double tap, swipe down, and swipe right have different purposes or functions. For instance, a double tap is often used for activating or executing the selected item rather than announcing it, while swipe gestures are primarily for navigation or moving through lists without explicitly announcing the active item. The specific role of each gesture is tailored to facilitate a smoother user experience based on how users interact with the touchscreen.