Final answer:
Joanne should choose to 'Insert page numbers' to automatically number each page in her document, which is more efficient and error-free compared to other methods.
Step-by-step explanation:
To number the pages in her document, Joanne should c. Insert page numbers. This is typically done using a word processor's built-in feature. For example, in Microsoft Word, Joanne can insert page numbers by going to the Insert tab and selecting the Page Number option. The page numbers will automatically update as pages are added or removed. This is a much more efficient and error-free method as compared to manually typing numbers on each page or using line numbering, which doesn't correspond to the page number. Moreover, applying heading styles is beneficial for structuring the document but doesn't address Joanne's need for page numbering.