Expert system can be expressed as?

(A) It provides tools for the management, delivery, tracking, and assessment of various types of employee learning and training.
(B) The set of business processes, culture, and behavior required to obtain value from investments in information systems.
(C) Intelligent technique for capturing tacit knowledge in a very specific and limited domain of human expertise, this knowledge is converted to rules that can be used throughout the entire organization.
(D) None of the above