What does it mean for an application to be standards-compliant?

For an application to be standards-compliant, it means that it adheres to established guidelines and protocols that are widely accepted in the industry. By using standard W3C code for HTML, scripting, and CSS, the application ensures compatibility across different platforms and devices. This is crucial for achieving a consistent user experience, improving accessibility, and enhancing interoperability with other web services and technologies.

Using standard coding practices also means that developers can leverage best practices and tools that are built around these standards, ultimately leading to better performance and maintainability of the application. Compliance with W3C standards helps to ensure that the application will render correctly in various web browsers, thus reaching a wider audience without being limited by proprietary or non-standard practices.

The other options do not accurately reflect what being standards-compliant entails. For instance, requiring pre-installation on devices, limiting access to certain browsers, or being unrestricted in data formats would not indicate adherence to standard practices. Instead, they may restrict usability or flexibility, which is contrary to the purpose of being standards-compliant.