The group that doesn't receive treatment/medicine.
Here's some advice;
take notes, pay attention in class, and use your textbook, if you can't find the answer look on the web, ask a friend, but never use brainly because people will say random stuff to get points.
Answer:
organ level
Explanation: because multiple types of tissues are working together.
The integumentary system (skin) has been called a membrane and an organ but, it is generally considered a system because it has organs that work together as a system. It is sometimes considered an organ because it contains several types of tissues and a membrane and it covers the body.
