The correct answer is A. Multiple Document Interface (MDI).
A multiple document interface (MDI) is a user interface (UI) metaphor that allows multiple documents to be displayed in a single window. The MDI was first introduced by Microsoft in its Windows 3.0 operating system.
In an MDI, each document is displayed in a separate child window. The parent window, which contains the child windows, is typically called the MDI frame. The MDI frame provides a common set of controls for all of the child windows, such as a menu bar, toolbar, and status bar.
The MDI is a popular UI metaphor for applications that need to display multiple documents, such as word processors, spreadsheets, and presentation programs.
The other options are incorrect.
- Single document interface (SDI) is a user interface (UI) metaphor that allows only one document to be displayed at a time.
- Single data interface (SDI) is a data access method that allows multiple applications to access the same data.
- System document interface (SDI) is a system interface that allows applications to access system documents.