The correct answer is D. Autoexec.bat.
Autoexec.bat is a batch file that is automatically run when MS-DOS is booted. It contains a list of commands that are executed every time the computer starts up. These commands can be used to set up the environment, load device drivers, and start programs.
Run.bat is a batch file that can be used to run a program or command. It is not automatically run when MS-DOS is booted.
Config.sys is a configuration file that is used to set up the environment for MS-DOS. It contains a list of commands that are executed before Autoexec.bat.
Config.bat is not a valid option.