A.) Valves, that’s the right answer
I believe c is the correct answer.
Answer:
The immune response is how your body recognizes and defends itself against bacteria, viruses, and substances that appear foreign and harmful.
Information
The immune system protects the body from possibly harmful substances by recognizing and responding to antigens. Antigens are substances (usually proteins) on the surface of cells, viruses, fungi, or bacteria. Nonliving substances such as toxins, chemicals, drugs, and foreign particles (such as a splinter) can also be antigens. The immune system recognizes and destroys, or tries to destroy, substances that contain antigens.
Your body's cells have proteins that are antigens. These include a group of antigens called HLA antigens. Your immune system learns to see these antigens as normal and usually does not react against them.
It is an example of addiction which is a bad habit that can lead to other health issues like depression
Heart. The reason behind this is harmful gases can cause many problems with the human body. It can effect the skin. Harming the skins natural barriers. It can harm the lungs. And your eyes are very soft. Your eyes cannot take that