What are the two basic styles of Windows interfaces?

The correct answer identifies the two basic styles of Windows interfaces as single-document interface (SDI) and multiple-document interface (MDI).

An SDI allows only one document to be opened in a single window. This approach simplifies navigation and operation, as the user focuses on one document at a time without the distractions of other open documents. It suits applications where interaction with multiple files simultaneously is not necessary or practical. Common examples of SDI applications include text editors and image viewers, where the user typically works with one file at a time.

On the other hand, an MDI supports multiple document windows within a single parent window. This means that users can work with several files simultaneously without opening multiple application instances. MDI is beneficial for applications where users need to compare or transfer data between multiple documents, such as graphic design or coding environments.

The other options represent different categories of interfaces but do not directly correspond to the styles of Windows interfaces. Command-line interface (CLI) and graphical user interface (GUI) are broader categories and encompass more than just Windows-based applications. ASCII and Unicode are character encoding standards irrelevant to interface styles, while web-based and local pertain to the environments in which applications operate rather than their user interface design styles.