Which answer choice below best defines the term "citator," within the context of conducting legal research?

A. This is a tool found on electronic legal research sites, such as Westlaw and Lexis Nexis, that flags specific cases that contain decisions by courts that demonstrate the effectiveness of child custody parenting plans.

B. This is a tool found on electronic legal research sites, such as Westlaw and Lexis Nexis, that flags specific cases based on the area of law addressed by the court and the length of the lawsuit from the date of filing to the date of completion.

C. This is a tool found on electronic legal research sites, such as Westlaw and Lexis Nexis, that flags specific cases containing scandalous content regarding divorces and child custody matters, and helps attorneys and paralegals locate potential clients.

D. This is a tool found on electronic legal research sites, such as Westlaw and Lexis Nexis, that flags specific cases with color-coded symbols designed to inform a user whether a case is good law, bad or overturned law, or the case has been distinguished and received potentially negative treatment by another court.