Explanation:

The correct option is (a) documentation. Documentation, in the context of software, refers to all written materials that describe the software, including its features, functions, and instructions on how to use it. A 'documentation manual' is specifically designed to guide users through the software's operation. Option (b) programming is the process of creating software, not a manual for using it. Option (c) technical describes the nature or complexity of information, but it is not the name of the manual itself. Option (d) user refers to the individual operating the software, not the manual that instructs them. Thus, documentation is the term for the manual that provides usage instructions.