Which redirection appends standard error to an existing file?

• A. command 2> File
• B. command > File
• C. command 2>> File
• D. command &> File

Answer: (C)

Appending the standard error stream requires using the error descriptor with the append operator. The correct form uses 2>>, which takes the stderr (descriptor 2) and appends it to the specified file. This means any new error output is added to the end of the file without altering what was already there, and if the file doesn’t exist it will be created.

In contrast, 2> overwrites the file with only the latest error, > writes stdout and overwrites the file, and &> redirects both stdout and stderr (usually overwriting) to the file.