The correct answer is C. BAT, because batch files are specifically designed to execute a sequence of commands automatically in Windows environments. They are commonly used for startup tasks such as launching applications, mapping network drives, setting environment variables, or running maintenance scripts.

According to the Quentin Docter – CompTIA A+ Complete Study Guide, batch files (.bat) are text-based scripts interpreted by the Windows Command Processor (cmd.exe). They are lightweight, easy to create, and can be placed directly in startup folders or scheduled through system tasks.

The Travis Everett & Andrew Hutz – All-in-One Exam Guide emphasizes that batch files are ideal for automation because they do not require compilation and can run without user interaction. This makes them well-suited for startup operations that must execute consistently every time the system boots or a user logs in.

The Mike Meyers / Mark Soper Lab Manual contrasts batch files with other file types: .sh files are used in Linux and macOS, .msi files are installer packages, and .exe files are compiled programs that may prompt user interaction or security warnings.

Because batch files are native to Windows, scriptable, and commonly used for startup automation, C. BAT is the correct answer.