Explanation:
In the backward chaining technique, used by the inference engine component of an expert system, the expert system starts with the goal, which is the then part,
Backward chaining is the process of working backward from the goal. It is used s an artificial intelligence application and proof application. The backward chaining can be implemented in logic programming.
Hence the then part is the correct answer.
Learn more about the backward chaining technique,
brainly.com/question/24178695.