An organization becomes on interest group when it becomes politically active, such as when an organization tries to change an amendment.
The American Medical Association is a professional association, and it does meet the definition of an economic interest group. It was founded in 1847.
Trade association
professional
yes
social interest group
social interest group
the American Medical Association and the National Rifle Association.
It is a single-interest firearm-related public interest group.
social interest group
They would be considered a labor interest group or a union.
National Rifle Association
economic