A Unique Feature of the KeyCite Service Not Present in Other

A unique feature of the KeyCite service not present in other citators is:

A) a one-to-four star system that indicates the extent to which citing cases discuss the case of interest.
B) headnotes that address only the tax issues in a case.
C) case evaluation symbols such as warning flags to indicate how the later court has treated a cited case.
D) All of the above features are only available in the KeyCite service.