Which are the physical (P), chemical (C), and biological (B) immune responses?

P: complement system; C: saliva; B: coughing

P: coughing; C: saliva; B: complement system

P: coughing; C: sneezing; B: complement system

P: complement system; C: saliva; B: sneezing

The answer is P: coughing; C: saliva; B: complement system.

Coughing is a physical immune response because it mechanically (physically) removes irritants and pathogens from the lungs. Sneezing is also the physical immune response.

Saliva is a chemical immune response because it contains different enzymes able to break down pathogens.

Complement system is a biological immune response because it activates biological molecules, such as antibodies, to remove pathogens from the organism.