The correct answer is B: Ctrl+Z. This shortcut is universally recognized across most applications, including word processors, graphic design software, and web browsers, as the command to undo the last action. It allows users to reverse a mistake, such as deleting text, moving an object, or applying incorrect formatting, thereby restoring the previous state of the document or application.
A: Ctrl+A is the shortcut to select all content within the active window or document. For instance, in a word processor, it would select all text; in a folder, it would select all files.
C: Ctrl+C is the shortcut to copy the currently selected item(s). This places a duplicate of the selected content onto the clipboard, from where it can be pasted elsewhere.
D: Ctrl+V is the shortcut to paste the content that is currently stored on the clipboard. This content would typically have been copied or cut using
Ctrl+CorCtrl+X, respectively.