The correct answer is D. Both a and b.
Copy and Xcopy are both DOS commands that can be used to copy files. Copy is an internal command, which means that it is stored in memory and does not need to be loaded from disk each time it is used. Xcopy is an external command, which means that it is stored on disk and needs to be loaded into memory each time it is used.
Copy can be used to copy a single file or multiple files. The syntax for Copy is as follows:
Copy source destination
The source is the file or files that you want to copy, and the destination is the location where you want to copy the files. For example, to copy the file “myfile.txt” to the directory “c:\myfiles”, you would use the following command:
Copy myfile.txt c:\myfiles
Xcopy can also be used to copy a single file or multiple files. The syntax for Xcopy is as follows:
Xcopy source destination [/a] [/b] [/c] [/d] [/e] [/f] [/g] [/h] [/i] [/j] [/k] [/l] [/m] [/n] [/o] [/p] [/q] [/r] [/s] [/t] [/u] [/v] [/w] [/x] [/y] [/z]
The source is the file or files that you want to copy, and the destination is the location where you want to copy the files. The options that are available with Xcopy are as follows:
/a: Copies only files that have the archive attribute set.
/b: Copies files in binary mode.
/c: Continues copying even if errors occur.
/d: Copies only files that do not exist in the destination directory.
/e: Copies directories and subdirectories, even if they are empty.
/f: Suppresses the confirmation prompt when overwriting existing files.
/g: Copies hidden and system files.
/h: Suppresses the display of file names that are longer than 8.3 characters.
/i: Retries copying a file if the first attempt fails.
/j: Copies files with long file names to a FAT32 destination.
/k: Copies file attributes.
/l: Lists the names of the files that would be copied.
/m: Copies only modified files.
/n: Creates new directories in the destination directory.
/o: Overwrites existing files without prompting.
/p: Pauses after each file is copied.
/q: Quiet mode. Suppresses all messages except error messages.
/r: Recursively copies subdirectories.
/s: Copies directories and subdirectories, including empty ones.
/t: Copies files in the order they would be listed by the DIR command.
/u: Copies only files that are newer than the files in the destination directory.
/v: Verifies that the files were copied correctly.
/w: Waits for a specified number of seconds before copying each file.
/x: Copies hidden and system files, even if the destination is on a FAT32 volume.
/y: Suppresses the prompt that asks if you want to overwrite an existing file.
/z: Copies files using Unicode.
As you can see, Xcopy is a much more powerful command than Copy. It offers a wide range of options that allow you to control exactly how files are copied.