Explanation/Reference:
A: Regardless of what type of data is associated with a theme (except for WMS themes, which represent externally rendered map layers), the MapViewer styling rules still need to be defined for each theme, and the styles referenced by the styling rules must exist and be stored in the database as part of the mapping metadata.
D: A WFS theme is a special kind of MapViewer theme that supports the rendering of data delivered using the Open GIS Consortium (OGC) Web Feature Service (WFS) protocol, specifically the WFS 1.0.0 implementation specification.
WFS theme are conceptually similar to geometry themes, and users are able to render and label features.
The WFS operations GetCapabilities, DescribeFeatureType, and GetFeature are used when rendering a WFS theme. When a WFS service is accessed, MapViewer caches the information about capabilities and feature types.
References: https://docs.oracle.com/cd/E12839_01/web.1111/e10145/vis_concepts.htm#JIMPV9548