CompTIA Linux+ XK0-006 (V8) Practice Question

The --update ( -u ) option tells Git to update the index only where an entry already exists. It therefore stages changes to tracked files-including deletions-without touching any brand-new, untracked paths. Using git add -u (optionally with a pathspec such as ".") achieves exactly what is required.

• git add -A or git add --all would also stage the new untracked files because it adds, modifies, and removes entries to match the working tree.
• git add . stages modifications to tracked files and adds new files found under the current directory (since Git 2.0, it also stages deletions), so the unwanted files would be included.
• git add -i enters interactive mode; it could accomplish the task, but only after extra manual steps, so it does not meet the constraint of a single non-interactive command.