Expert systems involve which of the following?

A) models of expert judgments in a given field
B) a series of relevant facts for a given field
C) inference rules to search the field's knowledge base
D) all of these

Expert Judgments

are assessments, insights, or decisions made by individuals or groups with specialized knowledge or training in a particular field.

Inference Rules

Rules that govern the logical steps allowing the deduction of conclusions from premises.