Which of the following describes a key characteristic of social media?

The key characteristic of social media is that it allows for real-time interaction and content sharing. This interactivity is essential to the nature of social media platforms, where users can post updates, comments, and engage in discussions instantaneously. This characteristic enables individuals and organizations to connect with a vast audience, share multimedia content, and engage in conversations that can happen in real-time, creating a dynamic and responsive communication environment.

In contrast, social media is not primarily a paid advertising service, as many platforms enable free user-generated content and communication alongside promotional content. It's also not exclusively used for professional networking; platforms like Facebook and Instagram serve broader social purposes. Finally, while some posts might be text-based, social media is characterized by its diverse range of content types, including images, videos, and live streams, rather than being limited to just text.