Which of the following allows formatting of text appearance in a resource's help section?

The reasoning behind the selection of rich text formatting options as the correct answer lies in its specific function related to the appearance and styling of text within content areas, including resources' help sections. Rich text formatting allows users to manipulate various aspects of text, such as font style, size, color, alignment, and the use of lists, links, and images. This capability is essential for enhancing readability and engagement in help sections, where clear and visually appealing communication is crucial.

In contrast, while other options like the resource viewer and admin configuration panel may play roles in the overall resource management or user interface, they do not directly deal with text formatting. Content management settings may pertain to broader organizational aspects of content but don't focus specifically on the nuanced styling features that rich text formatting options provide. Therefore, the specific functionality of rich text formatting is what makes it the right choice for controlling text appearance in a resource's help section.