Answer:
A Special Interest Group.
Explanation:
As the exercise suggests, given that Joe is a lobbyist who represents a certain industry, we can deduce that he represents a Special Interest Group; a community within an organization with an interest to advance in certain areas such as technology, politics, knowledge, etc. As such, he is meeting with several members of Congress to try to exert political influence by contributing funds to the lawmakers' election campaigns. Joe also is involved in a letter-writing campaign to promote his cause.
