Answer:
subject matter expert.
Step-by-step explanation:
Carl, a human resource professional, seeks out Joe while completing a job analysis to learn about what his position entails. Joe was recommended by his supervisor as someone who is highly knowledgeable and skilled and able to give unique information about the job. Joe is considered a subject matter expert. A subject matter expert is an individual who is very knowledgeable in a particular subject area and has profound expertise in that field. He/she is regarded as a knowledge tank in that field or subject area.