What feature suggests possible completions for the text being entered?

The correct answer is autocompletion, which is a feature designed to assist users by suggesting possible completions for the text they are currently typing. This functionality enhances user experience by speeding up text entry and reducing errors, as it narrows down options based on the characters already input. For instance, in a search bar or a form field, as a user begins typing, autocompletion provides a dropdown list of likely completions, allowing for quicker selection without needing to type the entire word or phrase.

Form validation, on the other hand, ensures that the user's input adheres to predefined criteria, such as format correctness or required fields but does not suggest text completions. Placeholder text serves as a cue to guide users on what type of information should be entered into a field but does not assist in real-time text completion. Live preview provides a real-time look at how content will appear once finalized, rather than offering suggestions for text input. All these features serve different functions, but autocompletion is specifically tailored to improve the efficiency and accuracy of user input as they type.