Which of the following is NOT a file extension for documents with macros?

The file extension .xlsx is not associated with documents that contain macros. In Microsoft Office applications, particularly Excel and Word, specific file extensions indicate the ability to run macros.

Files with the .docm and .dotm extensions are designed for Word documents that have macros enabled. The ".docm" extension is used for standard Word documents containing macros, while ".dotm" is used for template files that can also include macros. Similarly, the .xlsm extension is specific to Excel workbooks that can contain macros.

On the other hand, the .xlsx extension is utilized for standard Excel workbooks that do not include macros. This distinction is essential for users who want to maintain security or avoid unintended macro executions by choosing the appropriate file extension when saving their documents. Therefore, choosing .xlsx indicates that macros are not present, distinguishing it from the other options related to macro-enabled files.