Which of the following is not a text formatting command?

The correct answer is C, as CTRL+A is not a text formatting command. Instead, this keyboard shortcut is used to select all the text within a document or text field. This functionality allows users to highlight everything quickly for editing, copying, or formatting purposes.

In contrast, the other commands are specifically designed for formatting text. CTRL+B bolds the selected text, making it thicker and more prominent. CTRL+I italicizes the text, slanting it to the right to indicate emphasis or distinction. CTRL+U underlines the selected text, adding a line beneath it for added visibility. Each of these commands directly alters the appearance of the text, whereas CTRL+A is focused on selection rather than formatting.