Final answer:
To remove the Johnson E source from a document, you should use the 'Remove Source' feature in your word processor's citation tools, typically found under the 'References' tab.
Step-by-step explanation:
Removing a source from a document, such as the Johnson E source, typically refers to managing citations or bibliographic entries in a word processor like Microsoft Word. If you want to remove a source from the current document only, without affecting its presence in other documents or the source manager, you would use the 'Remove Source' feature. This could be done by accessing the citation tools in your word processor, usually found in the 'References' tab. Once there, you can manage sources and remove the one you no longer wish to include. It's important to understand that the 'Delete' key will only remove the citation from the text, but not the source itself from the document's source manager. The 'Ctrl + Del' option is not standard for citation management, and 'Cut and Paste' can be used to move text around but doesn't delete a source from the source manager.