An expert system is a software that(41)specialist knowledge-about a particular domain of(42)and is capable of making(43)decisions with in that domain. Although expert systems typically focus on a very narrow domain, they have achieved dramatic success with(44)problems, This has excited wide spread interest outside the research laboratories from which they emerged.Expert systems have given rise to a set of "knowledge engineering" methods constituting a new approach to design of high performance software system. This new approach represents an(45)change with revolutionary consequences.

A. develops
B. directory
C. effect
D. encapsulates
E. evolutionary