To correct grammar errors in a document, which feature must be activated?

Activating the spelling and grammar tools is essential for correcting grammar errors in a document. This feature not only identifies misused words and grammatical mistakes but also provides suggestions for corrections, enabling users to enhance the overall quality of their writing. By utilizing this tool, one can ensure that the text adheres to standard language conventions, making the document more professional and easier to understand.

The other features listed do not address grammar errors specifically. For instance, text alignment options relate primarily to the formatting and layout of the document rather than its content. The spell check only feature focuses solely on spelling mistakes, which may overlook important grammatical issues. Font options pertain to the visual styling of the text, such as typeface and size, and do not contribute to correcting language use in the document.